# Sort disjoint sublist

Sort disjoint sublist
You are encouraged to solve this task according to the task description, using any language you may know.

Given a list of values and a set of integer indices into that value list, the task is to sort the values at the given indices, but preserving the values at indices outside the set of those to be sorted.

Make your example work with the following list of values and set of indices:

values: [7, 6, 5, 4, 3, 2, 1, 0]
indices: {6, 1, 7}

Where the correct result would be:

[7, 0, 5, 4, 3, 2, 1, 6].

Note that for one based, rather than the zero-based indexing above, use the indices: {7, 2, 8}. The indices are described as a set rather than a list but any collection-type of those indices without duplication may be used as long as the example is insensitive to the order of indices given.

Cf.

procedure DisjointSort is

package Int_Io is new Integer_IO (Integer);

subtype Index_Range is Natural range 1 .. 8;
Input_Array : array (Index_Range) of Integer := (7, 6, 5, 4, 3, 2, 1, 0);

subtype Subindex_Range is Natural range 1 .. 3;
type Sub_Arrays is array (Subindex_Range) of Integer;

Sub_Index : Sub_Arrays := (7, 2, 8);
Sub_Array : Sub_Arrays;

-- reuse of the somehow generic GNAT.Bubble_Sort (for Ada05)

procedure Sort (Work_Array : in out Sub_Arrays) is
procedure Exchange (Op1, Op2 : Natural) is
Temp : Integer;
begin
Temp  := Work_Array (Op1);
Work_Array (Op1) := Work_Array (Op2);
Work_Array (Op2) := Temp;
end Exchange;

function Lt (Op1, Op2 : Natural) return Boolean is
begin
return (Work_Array (Op1) < Work_Array (Op2));
end Lt;
begin
GNAT.Bubble_Sort.Sort
(N => Subindex_Range'Last,
Xchg => Exchange'Unrestricted_Access,
Lt => Lt'Unrestricted_Access);
end Sort;

begin
-- as the positions are not ordered, first sort the positions
Sort (Sub_Index);
-- extract the values to be sorted
for I in Subindex_Range loop
Sub_Array (I) := Input_Array (Sub_Index (I));
end loop;
Sort (Sub_Array);
-- put the sorted values at the right place
for I in Subindex_Range loop
Input_Array (Sub_Index (I))  := Sub_Array (I);
end loop;

for I in Index_Range loop
Int_Io.Put (Input_Array (I), Width => 2);
end loop;
New_Line;

end DisjointSort;

## APL

∇SDS[⎕]∇

[0] Z←I SDS L
[1] L[I[⍋I]]←Z[⍋Z←L[I←∪I]]
[2] Z←L

Output:
⎕IO←0
6 1 7 SDS ⎕←⌽⍳8
7 6 5 4 3 2 1 0
7 0 5 4 3 2 1 6

## AppleScript

Works with versions of AppleScript from OS X 10.10 onwards

use AppleScript version "2.4"
use framework "Foundation"

-- disjointSort :: [Int] -> [Int] -> [Int]
on disjointSort(ixs, xs)
set ks to sort(ixs)
script nth -- 1-based index
on |λ|(k)
item (succ(k)) of xs
end |λ|
end script
set dct to mapFromList(zip(ks, sort(map(nth, ks))))

script build
on |λ|(x, i)
set mb to lookupDict(pred(i) as string, dct)
if Nothing of mb then
x
else
|Just| of mb
end if
end |λ|
end script
map(build, xs)
end disjointSort

on run
disjointSort({6, 1, 7}, {7, 6, 5, 4, 3, 2, 1, 0})
end run

-- GENERIC FUNCTIONS ----------------------------------------------------

-- Just :: a -> Maybe a
on Just(x)
{type:"Maybe", Nothing:false, Just:x}
end Just

-- Nothing :: Maybe a
on Nothing()
{type:"Maybe", Nothing:true}
end Nothing

-- length :: [a] -> Int
on |length|(xs)
set c to class of xs
if list is c or string is c then
length of xs
else
(2 ^ 29 - 1) -- (maxInt - simple proxy for non-finite)
end if
end |length|

-- lookupDict :: a -> Dict -> Maybe b
on lookupDict(k, dct)
set ca to current application
set v to (ca's NSDictionary's dictionaryWithDictionary:dct)'s objectForKey:k
if v ≠ missing value then
Just(item 1 of ((ca's NSArray's arrayWithObject:v) as list))
else
Nothing()
end if
end lookupDict

-- map :: (a -> b) -> [a] -> [b]
on map(f, xs)
tell mReturn(f)
set lng to length of xs
set lst to {}
repeat with i from 1 to lng
set end of lst to |λ|(item i of xs, i, xs)
end repeat
return lst
end tell
end map

-- mapFromList :: [(k, v)] -> Dict
on mapFromList(kvs)
set tpl to unzip(kvs)
script
on |λ|(x)
x as string
end |λ|
end script
(current application's NSDictionary's ¬
dictionaryWithObjects:(|2| of tpl) ¬
forKeys:map(result, |1| of tpl)) as record
end mapFromList

-- min :: Ord a => a -> a -> a
on min(x, y)
if y < x then
y
else
x
end if
end min

-- Lift 2nd class handler function into 1st class script wrapper
-- mReturn :: First-class m => (a -> b) -> m (a -> b)
on mReturn(f)
if class of f is script then
f
else
script
property |λ| : f
end script
end if
end mReturn

-- pred :: Enum a => a -> a
on pred(x)
x - 1
end pred

-- sort :: Ord a => [a] -> [a]
on sort(xs)
((current application's NSArray's arrayWithArray:xs)'s ¬
sortedArrayUsingSelector:"compare:") as list
end sort

-- succ :: Enum a => a -> a
on succ(x)
1 + x
end succ

-- take :: Int -> [a] -> [a]
-- take :: Int -> String -> String
on take(n, xs)
set c to class of xs
if list is c then
if 0 < n then
items 1 thru min(n, length of xs) of xs
else
{}
end if
else if string is c then
if 0 < n then
text 1 thru min(n, length of xs) of xs
else
""
end if
else if script is c then
set ys to {}
repeat with i from 1 to n
set v to xs's |λ|()
if missing value is v then
return ys
else
set end of ys to v
end if
end repeat
return ys
else
missing value
end if
end take

-- Tuple (,) :: a -> b -> (a, b)
on Tuple(a, b)
{type:"Tuple", |1|:a, |2|:b, length:2}
end Tuple

-- unzip :: [(a,b)] -> ([a],[b])
on unzip(xys)
set xs to {}
set ys to {}
repeat with xy in xys
set end of xs to |1| of xy
set end of ys to |2| of xy
end repeat
return Tuple(xs, ys)
end unzip

-- zip :: [a] -> [b] -> [(a, b)]
on zip(xs, ys)
zipWith(Tuple, xs, ys)
end zip

-- zipWith :: (a -> b -> c) -> [a] -> [b] -> [c]
on zipWith(f, xs, ys)
set lng to min(|length|(xs), |length|(ys))
if 1 > lng then return {}
set xs_ to take(lng, xs) -- Allow for non-finite
set ys_ to take(lng, ys) -- generators like cycle etc
set lst to {}
tell mReturn(f)
repeat with i from 1 to lng
set end of lst to |λ|(item i of xs_, item i of ys_)
end repeat
return lst
end tell
end zipWith
Output:
{7, 0, 5, 4, 3, 2, 1, 6}

## BBC BASIC

INSTALL @lib\$+"SORTLIB"
Sort% = FN_sortinit(0,0) : REM Ascending

DIM list%(7) : list%() = 7, 6, 5, 4, 3, 2, 1, 0
DIM indices%(2) : indices%() = 6, 1, 7

PROCsortdisjoint(list%(), indices%())
PRINT FNshowlist(list%())
END

DEF PROCsortdisjoint(l%(), i%())
LOCAL C%, i%, n%, t%()
n% = DIM(i%(),1)
DIM t%(n%)
FOR i% = 0 TO n%
t%(i%) = l%(i%(i%))
NEXT
C% = n% + 1
CALL Sort%, i%(0)
CALL Sort%, t%(0)
FOR i% = 0 TO n%
l%(i%(i%)) = t%(i%)
NEXT
ENDPROC

DEF FNshowlist(l%())
LOCAL i%, o\$
o\$ = "["
FOR i% = 0 TO DIM(l%(),1)
o\$ += STR\$(l%(i%)) + ", "
NEXT
= LEFT\$(LEFT\$(o\$)) + "]"

Output:

[7, 0, 5, 4, 3, 2, 1, 6]

## Bracmat

7 6 5 4 3 2 1 0:?values
& 6 1 7:?indices
& 0:?sortedValues:?sortedIndices
& whl
' ( !indices:%?i ?indices
& !values:? [!i %@?value ?
& (!value.)+!sortedValues:?sortedValues
& (!i.)+!sortedIndices:?sortedIndices
)
& whl
' ( !sortedIndices:(?i.)+?sortedIndices
& !values:?A [!i %@? ?Z
& !sortedValues:(?value.)+?sortedValues
& !A !value !Z:?values
)
& out\$!values;

Output:

7 0 5 4 3 2 1 6

## C

#include <stdio.h>

/* yes, bubble sort */
void bubble_sort(int *idx, int n_idx, int *buf)
{
int i, j, tmp;
#define for_ij for (i = 0; i < n_idx; i++) for (j = i + 1; j < n_idx; j++)
#define sort(a, b) if (a < b) { tmp = a; a = b; b = tmp;}
for_ij { sort(idx[j], idx[i]); }
for_ij { sort(buf[idx[j]], buf[idx[i]]);}
#undef for_ij
#undef sort
}

int main()
{
int values[] = {7, 6, 5, 4, 3, 2, 1, 0};
int idx[] = {6, 1, 7};
int i;

printf("before sort:\n");
for (i = 0; i < 8; i++)
printf("%d ", values[i]);

printf("\n\nafter sort:\n");
bubble_sort(idx, 3, values);

for (i = 0; i < 8; i++)
printf("%d ", values[i]);
printf("\n");

return 0;
}

## C#

using System;
using System.Linq;
using System.Collections.Generic;

public class Test
{
public static void Main()
{
var list = new List<int>{ 7, 6, 5, 4, 3, 2, 1, 0 };
list.SortSublist(6, 1, 7);
Console.WriteLine(string.Join(", ", list));
}
}

public static class Extensions
{
public static void SortSublist<T>(this List<T> list, params int[] indices)
where T : IComparable<T>
{
var sublist = indices.OrderBy(i => i)
.Zip(indices.Select(i => list[i]).OrderBy(v => v),
(Index, Value) => new { Index, Value });

foreach (var entry in sublist) {
list[entry.Index] = entry.Value;
}
}

}

## C++

#include <algorithm>
#include <iostream>
#include <iterator>
#include <vector>

template <typename ValueIterator, typename IndicesIterator>
void sortDisjoint(ValueIterator valsBegin, IndicesIterator indicesBegin,
IndicesIterator indicesEnd) {
std::vector<int> temp;

for (IndicesIterator i = indicesBegin; i != indicesEnd; ++i)
temp.push_back(valsBegin[*i]); // extract

std::sort(indicesBegin, indicesEnd); // sort
std::sort(temp.begin(), temp.end()); // sort a C++ container

std::vector<int>::const_iterator j = temp.begin();
for (IndicesIterator i = indicesBegin; i != indicesEnd; ++i, ++j)
valsBegin[*i] = *j; // replace
}

int main()
{
int values[] = { 7, 6, 5, 4, 3, 2, 1, 0 };
int indices[] = { 6, 1, 7 };

sortDisjoint(values, indices, indices+3);

std::copy(values, values + 8, std::ostream_iterator<int>(std::cout, " "));
std::cout << "\n";

return 0;
}
Output:
7 0 5 4 3 2 1 6
Translation of: Go

Solution that sorts using a custom iterator that iterates a disjoint sublist.

#include <algorithm>
#include <iostream>
#include <iterator>
#include <vector>

template <typename ValueIterator, typename IndicesIterator>
struct DisjointSubsetIterator :
public std::iterator<std::random_access_iterator_tag,
typename std::iterator_traits<ValueIterator>::value_type> {
typedef typename std::iterator_traits<ValueIterator>::value_type V;
ValueIterator valsBegin;
IndicesIterator i;
DisjointSubsetIterator() { }
DisjointSubsetIterator(const ValueIterator &_v, IndicesIterator _i) :
valsBegin(_v), i(_i) { }
DisjointSubsetIterator& operator++() { ++i; return *this; }
DisjointSubsetIterator operator++(int) {
DisjointSubsetIterator tmp = *this; ++(*this); return tmp; }
bool operator==(const DisjointSubsetIterator& y) { return i == y.i; }
bool operator!=(const DisjointSubsetIterator& y) { return i != y.i; }
V &operator*() { return valsBegin[*i]; }
DisjointSubsetIterator& operator--() { --i; return *this; }
DisjointSubsetIterator operator--(int) {
DisjointSubsetIterator tmp = *this; --(*this); return tmp; }
DisjointSubsetIterator& operator+=(int n) { i += n; return *this; }
DisjointSubsetIterator& operator-=(int n) { i -= n; return *this; }
DisjointSubsetIterator operator+(int n) {
DisjointSubsetIterator tmp = *this; return tmp += n; }
DisjointSubsetIterator operator-(int n) {
DisjointSubsetIterator tmp = *this; return tmp -= n; }
int operator-(const DisjointSubsetIterator &y) { return i - y.i; }
V &operator[](int n) { return *(*this + n); }
bool operator<(const DisjointSubsetIterator &y) { return i < y.i; }
bool operator>(const DisjointSubsetIterator &y) { return i > y.i; }
bool operator<=(const DisjointSubsetIterator &y) { return i <= y.i; }
bool operator>=(const DisjointSubsetIterator &y) { return i >= y.i; }
};
template <typename ValueIterator, typename IndicesIterator>
DisjointSubsetIterator<ValueIterator, IndicesIterator>
operator+(int n, const DisjointSubsetIterator<ValueIterator, IndicesIterator> &i) {
return i + n; }

template <typename ValueIterator, typename IndicesIterator>
void sortDisjoint(ValueIterator valsBegin, IndicesIterator indicesBegin,
IndicesIterator indicesEnd) {
std::sort(DisjointSubsetIterator<ValueIterator, IndicesIterator>(valsBegin, indicesBegin),
DisjointSubsetIterator<ValueIterator, IndicesIterator>(valsBegin, indicesEnd));
}

int main()
{
int values[] = { 7, 6, 5, 4, 3, 2, 1, 0 };
int indices[] = { 6, 1, 7 };

sortDisjoint(values, indices, indices+3);

std::copy(values, values + 8, std::ostream_iterator<int>(std::cout, " "));
std::cout << "\n";

return 0;
}
Output:
7 0 5 4 3 2 1 6

## Clojure

(defn disjoint-sort [coll idxs]
(let [val-subset (keep-indexed #(when ((set idxs) %) %2) coll)
replacements (zipmap (set idxs) (sort val-subset))]
(apply assoc coll (flatten (seq replacements)))))
Output:
user=> (disjoint-sort [7 6 5 4 3 2 1 0] #{6 1 7})
[7 0 5 4 3 2 1 6]

## Common Lisp

(defun disjoint-sort (values indices)
"Destructively perform a disjoin sublist sort on VALUES with INDICES."
(loop :for element :in
(sort (loop :for index :across indices
:collect (svref values index))
'<)
:for index :across (sort indices '<)
:do (setf (svref values index) element))
values)
Output:
CL-USER> (disjoint-sort #(7 6 5 4 3 2 1 0) #(6 1 7))
#(7 0 5 4 3 2 1 6)

## D

import std.algorithm, std.range, std.array;

void main() {
auto data = [7, 6, 5, 4, 3, 2, 1, 0];
auto indices = [6, 1, 7];

data.indexed(indices.sort()).sort();

assert(data == [7, 0, 5, 4, 3, 2, 1, 6]);
}

### Lower Level version

import std.algorithm: swap;

void disjointSort(T, U)(T[] arr, U[] indexes)
in {
if (arr.length == 0)
assert(indexes.length == 0);
else {
foreach (idx; indexes)
assert(idx >= 0 && idx < arr.length);
}
} body {
void quickSort(U* left, U* right) {
if (right > left) {
auto pivot = arr[left[(right - left) / 2]];
auto r = right, l = left;
do {
while (arr[*l] < pivot) l++;
while (arr[*r] > pivot) r--;
if (l <= r) {
swap(arr[*l], arr[*r]);
swap(l, r);
l++;
r--;
}
} while (l <= r);
quickSort(left, r);
quickSort(l, right);
}
}

if (arr.length == 0 || indexes.length == 0)
return;
quickSort(&indexes[0], &indexes[\$-1]);
}

void main() {
auto data = [7.0, 6.0, 5.0, 4.0, 3.0, 2.0, 1.0, 0.0];
auto indexes = [6, 1, 1, 7];
disjointSort(data, indexes);
assert(data == [7.0, 0.0, 5.0, 4.0, 3.0, 2.0, 1.0, 6.0]);
}

### Simple Alternative Version

import std.stdio, std.algorithm;

void main() {
auto data = [7.0, 6.0, 5.0, 4.0, 3.0, 2.0, 1.0, 0.0];
auto indexes = [6, 1, 1, 7]; // One duplicated added to test.

// Remove duplicates, in place:
indexes.length -= indexes.sort().uniq().copy(indexes).length;

foreach (i, idx; indexes)
swap(data[i], data[idx]);

data[0 .. indexes.length].sort();

foreach_reverse (i, idx; indexes)
swap(data[idx], data[i]);

assert(data == [7.0, 0.0, 5.0, 4.0, 3.0, 2.0, 1.0, 6.0]);
}

## EchoLisp

(define (sort-disjoint values indices)
(define sorted (list-sort <
(for/list [(v values) (i (in-naturals))]
#:when (member i indices) v)))

(for/list [(v values) (i (in-naturals))]
(if (not (member i indices)) v
(begin0
(first sorted)
(set! sorted (rest sorted))))))

(sort-disjoint '[7 6 5 4 3 2 1 0] {6 1 7}))

(7 0 5 4 3 2 1 6)

## Elena

ELENA 3.4 :

import extensions.
import system'routines.
import system'culture.

extension op
{
sortSublist : indices
[
var subList := indices orderBy(:x)(x);
zip(indices selectBy(:i)(self[i]);
orderBy(:x)(x)) by(:index:val)( { Index = index. Value = val. } );
toArray.

var list := self clone.
subList forEach(:r)
[
list[r Index] := r Value
].

^ list
]
}

public program
[
var list := ( 7, 6, 5, 4, 3, 2, 1, 0 ).

console writeLine(list sortSublist:(6, 1, 7); toLiteral).
]
Output:
7,0,5,4,3,2,1,6

## Elixir

defmodule Sort_disjoint do
def sublist(values, indices) when is_list(values) and is_list(indices) do
indices2 = Enum.sort(indices)
selected = select(values, indices2, 0, []) |> Enum.sort
replace(values, Enum.zip(indices2, selected), 0, [])
end

defp select(_, [], _, selected), do: selected
defp select([val|t], [i|rest], i, selected), do: select(t, rest, i+1, [val|selected])
defp select([_|t], indices, i, selected), do: select(t, indices, i+1, selected)

defp replace(values, [], _, list), do: Enum.reverse(list, values)
defp replace([_|t], [{i,v}|rest], i, list), do: replace(t, rest, i+1, [v|list])
defp replace([val|t], indices, i, list), do: replace(t, indices, i+1, [val|list])
end

values = [7, 6, 5, 4, 3, 2, 1, 0]
indices = [6, 1, 7]
IO.inspect Sort_disjoint.sublist(values, indices)
Output:
[7, 0, 5, 4, 3, 2, 1, 6]

## Erlang

-module( sort_disjoint ).

sublist( Values, Indices ) ->
Sorted_indices = lists:sort( Indices ),
Values_indexes = lists:seq( 1, erlang:length(Values) ),
{[], [], Indices_values} = lists:foldl( fun indices_values/2, {Values, Sorted_indices, []}, Values_indexes ),
Sorted_indices_values = lists:zip( Sorted_indices, lists:sort(Indices_values) ),
{Sorted_values, {[], []}} = lists:mapfoldl( fun merge/2, {Values, Sorted_indices_values}, Values_indexes ),
Sorted_values.

task() -> sublist( [7, 6, 5, 4, 3, 2, 1, 0], [7, 2, 8] ).

indices_values( Index, {[H | Values], [Index | Indices], Indices_values} ) -> {Values, Indices, [H | Indices_values]};
indices_values( _Index, {[_H | Values], Indices, Indices_values} ) -> {Values, Indices, Indices_values}.

merge( Index, {[_H | Values], [{Index, Value} | Sorted_indices_values]} ) -> {Value, {Values, Sorted_indices_values}};
merge( _Index, {[H | Values], Sorted_indices_values} ) -> {H, {Values, Sorted_indices_values}}.

Output:
[7,0,5,4,3,2,1,6]

## ERRE

PROGRAM DISJOINT

DIM LST%[7],INDICES%[2]

DIM L%[7],I%[2],Z%[2]
PROCEDURE SHOWLIST(L%[]->O\$)
LOCAL I%
O\$="["
FOR I%=0 TO UBOUND(L%,1) DO
O\$=O\$+STR\$(L%[I%])+", "
END FOR
O\$=LEFT\$(O\$,LEN(O\$)-2)+"]"
END PROCEDURE

PROCEDURE SORT(Z%[]->Z%[])
LOCAL N%,P%,FLIPS%
P%=UBOUND(Z%,1)
FLIPS%=TRUE
WHILE FLIPS% DO
FLIPS%=FALSE
FOR N%=0 TO P%-1 DO
IF Z%[N%]>Z%[N%+1] THEN SWAP(Z%[N%],Z%[N%+1]) FLIPS%=TRUE
END FOR
END WHILE
END PROCEDURE

PROCEDURE SortDisJoint(L%[],I%[]->L%[])
LOCAL J%,N%
LOCAL DIM T%[2]

N%=UBOUND(I%,1)
FOR J%=0 TO N% DO
T%[J%]=L%[I%[J%]]
END FOR
SORT(I%[]->I%[])
SORT(T%[]->T%[])
FOR J%=0 TO N% DO
L%[I%[J%]]=T%[J%]
END FOR
END PROCEDURE

BEGIN
LST%[]=(7,6,5,4,3,2,1,0)
INDICES%[]=(6,1,7)
SortDisJoint(LST%[],INDICES%[]->LST%[])
ShowList(LST%[]->O\$)
PRINT(O\$)
END PROGRAM
Output:
[ 7, 0, 5, 4, 3, 2, 1, 6]

## Euphoria

include sort.e

function uniq(sequence s)
sequence out
out = s[1..1]
for i = 2 to length(s) do
if not find(s[i], out) then
out = append(out, s[i])
end if
end for
return out
end function

function disjointSort(sequence s, sequence idx)
sequence values
idx = uniq(sort(idx))
values = repeat(0, length(idx))
for i = 1 to length(idx) do
values[i] = s[idx[i]]
end for
values = sort(values)
for i = 1 to length(idx) do
s[idx[i]] = values[i]
end for
return s
end function

constant data = {7, 6, 5, 4, 3, 2, 1, 0}
constant indexes = {7, 2, 8}

Output:

{7,0,5,4,3,2,1,6}

## F#

Translation of: Python

Works with arrays instead of lists because this algorithm is more efficient with a random access collection type. Returns a copy of the array, as is usually preferred in F#.

let sortDisjointSubarray data indices =
let indices = Set.toArray indices // creates a sorted array
let result = Array.copy data
Array.map (Array.get data) indices
|> Array.sort
|> Array.iter2 (Array.set result) indices
result

printfn "%A" (sortDisjointSubarray [|7;6;5;4;3;2;1;0|] (set [6;1;7]))

## Factor

: disjoint-sort ( values indices -- seq )
over <enumerated> nths unzip swap [ natural-sort ] [email protected]
pick [ set-nth ] curry 2each ;
Output:
IN: scratchpad { 7 6 5 4 3 2 1 0 } { 6 1 7 } disjoint-sort .
{ 7 0 5 4 3 2 1 6 }

## Fortran

Works with: Fortran version 90 and later
program Example
implicit none

integer :: array(8) = (/ 7, 6, 5, 4, 3, 2, 1, 0 /)
integer :: indices(3) = (/ 7, 2, 8 /)

! In order to make the output insensitive to index order
! we need to sort the indices first
call Isort(indices)

! Should work with any sort routine as long as the dummy
! argument array has been declared as an assumed shape array
! Standard insertion sort used in this example
call Isort(array(indices))

write(*,*) array

contains

subroutine Isort(a)
integer, intent(in out) :: a(:)
integer :: temp
integer :: i, j

do i = 2, size(a)
j = i - 1
temp = a(i)
do while (j>=1 .and. a(j)>temp)
a(j+1) = a(j)
j = j - 1
end do
a(j+1) = temp
end do

end subroutine Isort
end program Example

Output

7           0           5           4           3           2           1           6

## Go

package main

import (
"fmt"
"sort"
)

func main() {
// givens
values := []int{7, 6, 5, 4, 3, 2, 1, 0}
indices := map[int]int{6: 0, 1: 0, 7: 0}

orderedValues := make([]int, len(indices))
orderedIndices := make([]int, len(indices))
i := 0
for j := range indices {
// validate that indices are within list boundaries
if j < 0 || j >= len(values) {
fmt.Println("Invalid index: ", j)
return
}
// extract elements to sort
orderedValues[i] = values[j]
orderedIndices[i] = j
i++
}
// sort
sort.Ints(orderedValues)
sort.Ints(orderedIndices)

fmt.Println("initial:", values)
// replace sorted values
for i, v := range orderedValues {
values[orderedIndices[i]] = v
}
fmt.Println("sorted: ", values)
}

Output:

initial: [7 6 5 4 3 2 1 0]
sorted:  [7 0 5 4 3 2 1 6]

Alternative algorithm, sorting in place through the extra level of indirection.

Compared to the strategy of extract-sort-replace, this strategy avoids the space overhead of the work area and the time overhead of extracting and reinserting elements. At some point however, the cost of indirection multiplied by O(log n) would dominate, and extract-sort-replace would become preferable.

package main

import (
"fmt"
"sort"
)

// type and methods satisfying sort.Interface
type subListSortable struct {
values sort.Interface
indices []int
}

func (s subListSortable) Len() int {
return len(s.indices)
}

func (s subListSortable) Swap(i, j int) {
s.values.Swap(s.indices[i], s.indices[j])
}

func (s subListSortable) Less(i, j int) bool {
return s.values.Less(s.indices[i], s.indices[j])
}

func main() {
// givens
values := []int{7, 6, 5, 4, 3, 2, 1, 0}
indices := map[int]int{6: 0, 1: 0, 7: 0}

// make ordered list of indices for sort methods
ordered := make([]int, len(indices))
if len(indices) > 0 {
i := 0
for j := range indices {
ordered[i] = j
i++
}
sort.Ints(ordered)

// validate that indices are within list boundaries
if ordered[0] < 0 {
fmt.Println("Invalid index: ", ordered[0])
return
}
if ordered[len(ordered)-1] >= len(values) {
fmt.Println("Invalid index: ", ordered[len(ordered)-1])
return
}
}

// instantiate sortable type and sort
s := subListSortable{sort.IntSlice(values), ordered}
fmt.Println("initial:", s.values)
sort.Sort(s)
fmt.Println("sorted: ", s.values)
}

## Groovy

Groovy allows List-valued indexing to "gather" and "scatter" arbitrary sublists, making the solution almost trivial.

def sparseSort = { a, indices = ([] + (0..<(a.size()))) ->
indices.sort().unique()
a[indices] = a[indices].sort()
a
}

Test:

def a = [7, 6, 5, 4, 3, 2, 1, 0]

println a
println sparseSort(a, []) // no indices to sort
println a
println sparseSort(a, [6,1,7]) // suggested sample indices
println a
println sparseSort(a) // default == sort all
println a

Output:

[7, 6, 5, 4, 3, 2, 1, 0]
[7, 6, 5, 4, 3, 2, 1, 0]
[7, 6, 5, 4, 3, 2, 1, 0]
[7, 0, 5, 4, 3, 2, 1, 6]
[7, 0, 5, 4, 3, 2, 1, 6]
[0, 1, 2, 3, 4, 5, 6, 7]
[0, 1, 2, 3, 4, 5, 6, 7]

Here are three variations on the solution: using ordinary lists, immutable "boxed" arrays, and mutable "unboxed" arrays.

import qualified Data.Array as A
import Data.Array.IArray
import Data.Array.ST
import Data.List
import Data.List.Utils

-- Partition 'xs' according to whether their element indices are in 'is'. Sort
-- the sublist corresponding to 'is', merging the result with the remainder of
-- the list.
disSort1
:: (Ord a, Num a, Enum a, Ord b)
=> [b] -> [a] -> [b]
disSort1 xs is =
let is_ = sort is
(sub, rest) = partition ((`elem` is_) . fst) \$ zip [0 ..] xs
in map snd . merge rest . zip is_ . sort \$ map snd sub

-- Convert the list to an array. Extract the sublist corresponding to the
-- indices 'is'. Sort the sublist, replacing those elments in the array.
disSort2
:: (Ord a)
=> [a] -> [Int] -> [a]
disSort2 xs is =
let as = A.listArray (0, length xs - 1) xs
sub = zip (sort is) . sort \$ map (as !) is
in elems \$ as // sub

-- Similar to disSort2, but using mutable arrays. The sublist is updated
-- "in place", rather than creating a new array. However, this is not visible
-- to a caller.
disSort3 :: [Int] -> [Int] -> [Int]
disSort3 xs is =
elems . runSTUArray \$
do as <- newListArray (0, length xs - 1) xs
sub <- (zip (sort is) . sort) Control.Applicative.<\$> mapM (readArray as) is
mapM_ (uncurry (writeArray as)) sub
return as

main :: IO ()
main = do
let xs = [7, 6, 5, 4, 3, 2, 1, 0]
is = [6, 1, 7]
print \$ disSort1 xs is
print \$ disSort2 xs is
print \$ disSort3 xs is

Or, in terms of Data.Map:

import Data.Map as M (fromList, keys, lookup)
import Data.Maybe (mapMaybe)
import Data.List (sort)

disjointSort :: [Int] -> [Int] -> [Int]
disjointSort ixs xs =
let dctAll = fromList \$ zip xs [0 ..]
ks = sort ixs
dctIx = fromList \$ zip ks \$ sort (mapMaybe (`M.lookup` dctAll) ks)
in mapMaybe
(\k ->
let mb = M.lookup k dctIx
in case mb of
Nothing -> M.lookup k dctAll
_ -> mb)
(keys dctAll)

main :: IO ()
main = print \$ disjointSort [6, 1, 7] [7, 6, 5, 4, 3, 2, 1, 0]
Output:
[7,0,5,4,3,2,1,6]

## Icon and Unicon

Icon's lists are 1-based, so the example uses (7, 2, 8) as the indices, not (6, 1 7).

link sort # get the 'isort' procedure for sorting a list

procedure sortDisjoint (items, indices)
indices := isort (indices) # sort indices into a list
result := copy (items)
values := []
every put (values, result[!indices])
values := isort (values)
every result[!indices] := pop (values)
return result
end

procedure main ()
# set up and do the sort
items := [7, 6, 5, 4, 3, 2, 1, 0]
indices := set(7, 2, 8) # note, Icon lists 1-based
result := sortDisjoint (items, indices)
# display result
every writes (!items || " ")
write ()
every writes (!indices || " ")
write ()
every writes (!result || " ")
write ()
end

Output:

7 6 5 4 3 2 1 0
2 7 8
7 0 5 4 3 2 1 6
The expression !indices generates the value of each index in turn, so the line
every put (values, result[!indices])
effectively loops through each index, putting result[index] into the list 'values'.

## Io

Io does not come with a set type.

List disjointSort := method(indices,
sortedIndices := indices unique sortInPlace
sortedValues := sortedIndices map(idx,at(idx)) sortInPlace
sortedValues foreach(i,v,atPut(sortedIndices at(i),v))
self
)

list(7,6,5,4,3,2,1,0) disjointSort(list(6,1,7)) println
Output:
list(7, 0, 5, 4, 3, 2, 1, 6)

## J

Note that the task requires us to ignore the order of the indices.

7 6 5 4 3 2 1 0 (/:[email protected]:{`[`]}~ /:[email protected]~.) 6 1 7
7 0 5 4 3 2 1 6

Compare this with:

6 1 7 /:[email protected]:{`[`]} 7 6 5 4 3 2 1 0
7 1 5 4 3 2 0 6

Here, the order of the indices specifies the order we want the selected items to be sorted in: 7 1 5 4 3 2 0 6

## Java

Works with: Java version 1.5+

This function will modify the index array and the values list.

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;

public class Disjoint {
public static <T extends Comparable<? super T>> void sortDisjoint(
List<T> array, int[] idxs) {
Arrays.sort(idxs);
List<T> disjoint = new ArrayList<T>();
for (int idx : idxs) {
}
Collections.sort(disjoint);
int i = 0;
for (int idx : idxs) {
array.set(idx, disjoint.get(i++));
}
}

public static void main(String[] args) {
List<Integer> list = Arrays.asList(7, 6, 5, 4, 3, 2, 1, 0);
int[] indices = {6, 1, 7};
System.out.println(list);
sortDisjoint(list, indices);
System.out.println(list);
}
}
Output:
[7, 6, 5, 4, 3, 2, 1, 0]
[7, 0, 5, 4, 3, 2, 1, 6]
Works with: Java version 1.5+
Translation of: Go

Shorter solution that sorts a list "wrapper" which represents a "view" into the disjoint sublist of the list.

import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.AbstractList;

public class Disjoint {
public static <T extends Comparable<? super T>> void sortDisjoint(
final List<T> array, final int[] idxs) {
Arrays.sort(idxs);
Collections.sort(new AbstractList<T>() {
public int size() { return idxs.length; }
public T get(int i) { return array.get(idxs[i]); }
public T set(int i, T x) { return array.set(idxs[i], x); }
});
}

public static void main(String[] args) {
List<Integer> list = Arrays.asList(7, 6, 5, 4, 3, 2, 1, 0);
int[] indices = {6, 1, 7};
System.out.println(list);
sortDisjoint(list, indices);
System.out.println(list);
}
}
Output:
[7, 6, 5, 4, 3, 2, 1, 0]
[7, 0, 5, 4, 3, 2, 1, 6]

## JavaScript

### ES5

#### Iterative

Does not check for duplicate indices.

function sort_disjoint(values, indices) {
var sublist = [];
indices.sort(function(a, b) { return a > b; });

for (var i = 0; i < indices.length; i += 1) {
sublist.push(values[indices[i]]);
}

sublist.sort(function(a, b) { return a < b; });

for (var i = 0; i < indices.length; i += 1) {
values[indices[i]] = sublist.pop();
}

return values;
}

#### Functional

(function () {
'use strict';

// disjointSort :: [a] -> [Int] -> [a]
function disjointSort(xs, indices) {

var indicesSorted = indices.sort(),
subsetSorted = indicesSorted
.map(function (i) {
return xs[i];
})
.sort();

return xs
.map(function (x, i) {
var iIndex = indicesSorted.indexOf(i);

return iIndex !== -1 ? (
subsetSorted[iIndex]
) : x;
});
}

return disjointSort([7, 6, 5, 4, 3, 2, 1, 0], [6, 1, 7])

})();
Output:
[7, 0, 5, 4, 3, 2, 1, 6]

### ES6

(() => {
'use strict';

// disjointSort :: [Int] -> [Int] -> [Int]
const disjointSort = (indices, xs) => {
const
ks = sort(indices),
dct = mapFromList(
zip(ks, sort(map(k => xs[k], ks)))
);
return map(
(x, i) => {
const v = dct[i.toString()];
return undefined !== v ? v : x;
},
xs
);
};

// main :: IO ()
const main = () =>
showLog(
disjointSort(
[6, 1, 7],
[7, 6, 5, 4, 3, 2, 1, 0]
)
);

// GENERIC FUNCTIONS ----------------------------

// length :: [a] -> Int
const length = xs => xs.length || Infinity;

// map :: (a -> b) -> [a] -> [b]
const map = (f, xs) => xs.map(f);

// mapFromList :: [(k, v)] -> Dict
const mapFromList = kvs =>
kvs.reduce(
(a, kv) => {
const k = kv[0];
return Object.assign(a, {
[(('string' === typeof k) && k) || showJSON(k)]: kv[1]
});
}, {}
);

// showJSON :: a -> String
const showJSON = x => JSON.stringify(x);

// showLog :: a -> IO ()
const showLog = (...args) =>
console.log(
args
.map(JSON.stringify)
.join(' -> ')
);

// sort :: Ord a => [a] -> [a]
const sort = xs => xs.slice()
.sort((a, b) => a < b ? -1 : (a > b ? 1 : 0));

// take :: Int -> [a] -> [a]
// take :: Int -> String -> String
const take = (n, xs) =>
xs.constructor.constructor.name !== 'GeneratorFunction' ? (
xs.slice(0, n)
) : [].concat.apply([], Array.from({
length: n
}, () => {
const x = xs.next();
return x.done ? [] : [x.value];
}));

// Tuple (,) :: a -> b -> (a, b)
const Tuple = (a, b) => ({
type: 'Tuple',
'0': a,
'1': b,
length: 2
});

// Use of `take` and `length` here allows for zipping with non-finite
// lists - i.e. generators like cycle, repeat, iterate.

// zip :: [a] -> [b] -> [(a, b)]
const zip = (xs, ys) => {
const lng = Math.min(length(xs), length(ys));
return Infinity !== lng ? (() => {
const bs = take(lng, ys);
return take(lng, xs).map((x, i) => Tuple(x, bs[i]));
})() : zipGen(xs, ys);
};

// MAIN ---
return main();
})();
Output:
[7, 0, 5, 4, 3, 2, 1, 6]

## jq

We define a jq function, disjointSort, that accepts the array of values as input, but for clarity we first define a utility function for updating an array at multiple places:

def setpaths(indices; values):
reduce range(0; indices|length) as \$i
(.; .[indices[\$i]] = values[\$i]);

def disjointSort(indices):
(indices|unique) as \$ix # "unique" sorts
# Set \$sorted to the sorted array of values at \$ix:
| ([ .[ \$ix[] ] ] | sort) as \$sorted
| setpaths( \$ix; \$sorted) ;
Example:

[7, 6, 5, 4, 3, 2, 1, 0] | disjointSort( [6, 1, 7] )
produces:

[7,0,5,4,3,2,1,6]

## Julia

Works with: Julia version 0.6
function sortselected(a::AbstractVector{<:Real}, s::AbstractVector{<:Integer})
sel = unique(sort(s))
if sel[1] < 1 || length(a) < sel[end]
throw(BoundsError())
end
b = collect(copy(a))
b[sel] = sort(b[sel])
return b
end

a = [7, 6, 5, 4, 3, 2, 1, 0]
sel = [7, 2, 8]
b = sortselected(a, sel)

println("Original: \$a\n\tsorted on \$sel\n -> sorted array: \$b")
Output:
Original: [7, 6, 5, 4, 3, 2, 1, 0]
sorted on [7, 2, 8]
-> sorted array: [7, 0, 5, 4, 3, 2, 1, 6]

## K

{@[x;[email protected]<y;:;[email protected]<a:[email protected]]}[7 6 5 4 3 2 1 0;6 1 7]
7 0 5 4 3 2 1 6

### Another way

sort : {x[<x]}
nums : 7 6 5 4 3 2 1 0
i : sort 6 1 7
nums[i] : sort nums[i]
nums
7 0 5 4 3 2 1 6

## Kotlin

// version 1.1.51

/* in place sort */
fun IntArray.sortDisjoint(indices: Set<Int>) {
val sortedSubset = this.filterIndexed { index, _ -> index in indices }.sorted()
if (sortedSubset.size < indices.size)
throw IllegalArgumentException("Argument set contains out of range indices")
indices.sorted().forEachIndexed { index, value -> this[value] = sortedSubset[index] }
}

fun main(args: Array<String>) {
val values = intArrayOf(7, 6, 5, 4, 3, 2, 1, 0)
val indices = setOf(6, 1, 7)
println("Original array : \${values.asList()} sorted on indices \$indices")
values.sortDisjoint(indices)
println("Sorted array  : \${values.asList()}")
}

Output:
Original array : [7, 6, 5, 4, 3, 2, 1, 0] sorted on indices [6, 1, 7]
Sorted array   : [7, 0, 5, 4, 3, 2, 1, 6]

## Lua

values  = { 7, 6, 5, 4, 3, 2, 1, 0 }
indices = { 6, 1, 7 }

i = 1 -- discard duplicates
while i < #indices do
j = i + 1
while j < #indices do
if indices[i] == indices[j] then
table.remove( indices[j] )
end
j = j + 1
end
i = i + 1
end

for i = 1, #indices do
indices[i] = indices[i] + 1 -- the tables of lua are one-based
end

vals = {}
for i = 1, #indices do
vals[i] = values[ indices[i] ]
end

table.sort( vals )
table.sort( indices )

for i = 1, #indices do
values[ indices[i] ] = vals[i]
end

for i = 1, #values do
io.write( values[i], " " )
end
7  0  5  4  3  2  1  6

## Maple

sortDisjoint := proc(values, indices::set)
local vals,inds,i:
vals := sort([seq(values[i], i in indices)]):
inds := sort(convert(indices, Array)):
for i to numelems(vals) do
values(inds[i]) := vals[i]:
od:
end proc:
tst := Array([7,6,5,4,3,2,1,0]):
sortDisjoint(tst,{7,2,8});
Output:
[7 0 5 4 3 2 1 6]

## Mathematica

Values = { 7, 6, 5, 4, 3, 2, 1, 0} ; Indices = { 7, 2, 8 };
Values[[Sort[Indices]]] = Sort[Values[[Indices]]];

Values
-> { 7, 0, 5, 4, 3, 2, 1, 6 }

## NetRexx

/* NetRexx */
options replace format comments java crossref symbols nobinary

runSample(arg)
return

-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method sortDisjoint(oldList, indices) public static
newList = oldList.space()
if indices.words() > 1 then do -- only do work if we need to
subList = ArrayList()
idxList = ArrayList()
-- pick the input list apart
loop ix = 1 to indices.words()
iw = indices.word(ix)
nw = oldList.word(iw)
if iw > oldList.words() then signal ArrayIndexOutOfBoundsException()
if iw < 1 then signal ArrayIndexOutOfBoundsException()
end ix
Collections.sort(subList) -- sort sublist
Collections.sort(idxList) -- sort indices
-- put it all back together
loop kx = 0 to subList.size() - 1
kk = Rexx subList.get(kx)
ii = Rexx idxList.get(kx)
newList = newList.subword(1, ii - 1) kk newList.subword(ii + 1)
end kx
end
return newList

-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
method runSample(arg) private static
parse arg vList ',' iList
if vList = '' then vList = 7 6 5 4 3 2 1 0
if iList = '' then iList = 7 2 8
rList = sortDisjoint(vList, iList)
say 'In: ' vList.space
say 'Out:' rList.space
say 'Idx:' iList.space
return

Output:
In:  7 6 5 4 3 2 1 0
Out: 7 0 5 4 3 2 1 6
Idx: 7 2 8

## Nial

Works with: Q'Nial Version 6.3

values := [7, 6, 5, 4, 3, 2, 1, 0]
indices := sortup [6, 1, 7]
values#indices := sortup values#indices
7 0 5 4 3 2 1 6

## Nim

import algorithm

proc sortDisjoinSublist[T](data: var seq[T], indices: seq[int]) =
var indices = indices
sort indices, cmp[T]

var values: seq[T] = @[]
for i in indices: values.add data[i]
sort values, cmp[T]

for j, i in indices: data[i] = values[j]

var d = @[7, 6, 5, 4, 3, 2, 1, 0]
sortDisjoinSublist(d, @[6, 1, 7])
echo d

Output:

@[7, 0, 5, 4, 3, 2, 1, 6]

## Objective-C

Translation of: Go

Sorts an array "wrapper" which represents a "view" into the disjoint sublist of the array.

#import <Foundation/Foundation.h>

@interface DisjointSublistView : NSMutableArray {
NSMutableArray *array;
int *indexes;
int num_indexes;
}
- (instancetype)initWithArray:(NSMutableArray *)a andIndexes:(NSIndexSet *)ind;
@end

@implementation DisjointSublistView
- (instancetype)initWithArray:(NSMutableArray *)a andIndexes:(NSIndexSet *)ind {
if ((self = [super init])) {
array = a;
num_indexes = [ind count];
indexes = malloc(num_indexes * sizeof(int));
for (NSUInteger i = [ind firstIndex], j = 0; i != NSNotFound; i = [ind indexGreaterThanIndex:i], j++)
indexes[j] = i;
}
return self;
}
- (void)dealloc {
free(indexes);
}
- (NSUInteger)count { return num_indexes; }
- (id)objectAtIndex:(NSUInteger)i { return array[indexes[i]]; }
- (void)replaceObjectAtIndex:(NSUInteger)i withObject:(id)x { array[indexes[i]] = x; }
@end

@interface NSMutableArray (SortDisjoint)
- (void)sortDisjointSublist:(NSIndexSet *)indexes usingSelector:(SEL)comparator;
@end
@implementation NSMutableArray (SortDisjoint)
- (void)sortDisjointSublist:(NSIndexSet *)indexes usingSelector:(SEL)comparator {
DisjointSublistView *d = [[DisjointSublistView alloc] initWithArray:self andIndexes:indexes];
[d sortUsingSelector:comparator];
}
@end

int main(int argc, const char *argv[]) {
@autoreleasepool {

NSMutableArray *a = [@[@7, @6, @5, @4, @3, @2, @1, @0] mutableCopy];
NSMutableIndexSet *ind = [NSMutableIndexSet indexSet];
[a sortDisjointSublist:ind usingSelector:@selector(compare:)];
NSLog(@"%@", a);

}
return 0;
}
Output:
(
7,
0,
5,
4,
3,
2,
1,
6
)

## OCaml

With arrays:

let disjoint_sort cmp values indices =
let temp = Array.map (Array.get values) indices in
Array.sort cmp temp;
Array.sort compare indices;
Array.iteri (fun i j -> values.(j) <- temp.(i)) indices

let () =
let values = [| 7; 6; 5; 4; 3; 2; 1; 0 |]
and indices = [| 6; 1; 7 |] in
disjoint_sort compare values indices;
Array.iter (Printf.printf " %d") values;
print_newline()

With lists:

let disjoint_sort cmp values indices =
let indices = List.sort compare indices in
let rec aux acc j = function
| (i::iq), (v::vq) when i = j ->
aux (v::acc) (succ j) (iq, vq)
| [], _ -> acc
| il, (_::vq) ->
aux acc (succ j) (il, vq)
| _, [] ->
invalid_arg "index out of bounds"
in
let temp = aux [] 0 (indices, values) in
let temp = List.sort cmp temp in
let rec aux acc j = function
| (i::iq), (_::vq), (r::rq) when i = j ->
aux (r::acc) (succ j) (iq, vq, rq)
| [], vl, _ ->
List.rev_append acc vl
| il, (v::vq), rl ->
aux (v::acc) (succ j) (il, vq, rl)
| (_::_, [], _) ->
assert false
in
aux [] 0 (indices, values, temp)

let () =
let values = [ 7; 6; 5; 4; 3; 2; 1; 0 ]
and indices = [ 6; 1; 7 ] in
let res = disjoint_sort compare values indices in
List.iter (Printf.printf " %d") res;
print_newline()

## ooRexx

data = .array~of(7, 6, 5, 4, 3, 2, 1, 0)
-- this could be a list, array, or queue as well because of polymorphism
-- also, ooRexx arrays are 1-based, so using the alternate index set for the
-- problem.
indexes = .set~of(7, 2, 8)
call disjointSorter data, indexes

say "Sorted data is: ["data~toString("l", ", ")"]"

::routine disjointSorter
use arg data, indexes
temp = .array~new(indexes~items)
-- we want to process these in a predictable order, so make an array
tempIndexes = indexes~makearray
-- we can't just assign things back in the same order. The expected
-- result requires the items be inserted back in first-to-last index
-- order, so we need to sort the index values too
tempIndexes~sortWith(.numberComparator~new)
do index over tempIndexes
temp~append(data[index])
end
-- sort as numbers
temp~sortwith(.numberComparator~new)

do i = 1 to tempIndexes~items
data[tempIndexes[i]] = temp[i]
end

-- a custom comparator that sorts strings as numeric values rather than
-- strings
::class numberComparator subclass comparator
::method compare
use strict arg left, right
-- perform the comparison on the names. By subtracting
-- the two and returning the sign, we give the expected
-- results for the compares
return (left - right)~sign
Output:
Sorted data is: [7, 0, 5, 4, 3, 2, 1, 6]

## Order

#include <order/interpreter.h>

#define ORDER_PP_DEF_8sort_disjoint_sublist ORDER_PP_FN( \
8fn(8L, 8I, \
8lets((8I, 8seq_sort(8less, 8tuple_to_seq(8I))) \
(8J, \
8seq_sort(8less, 8seq_map(8fn(8X, 8seq_at(8X, 8L)), 8I))), \
8replace(8L, 8I, 8J))) )

#define ORDER_PP_DEF_8replace ORDER_PP_FN( \
8fn(8L, 8I, 8V, \
8if(8is_nil(8I), \
8L, \
8seq_tail(8I), 8seq_tail(8V)))) )

ORDER_PP(
8sort_disjoint_sublist(8seq(7, 6, 5, 4, 3, 2, 1, 0), 8tuple(6, 1, 7))
)

## PARI/GP

sortsome(v,which)={
my(x=sum(i=1,#which,1<<(which[i]-1)),u=vecextract(v,x));
u=vecsort(u);
which=vecsort(which);
for(i=1,#which,v[which[i]]=u[i]);
v
};

## Perl

#!/usr/bin/perl -w
use strict ;

# this function sorts the array in place
sub disjointSort {
my ( \$values , @indices ) = @_ ;

@{\$values}[ sort @indices ] = sort @{\$values}[ @indices ] ;
}

my @values = ( 7 , 6 , 5 , 4 , 3 , 2 , 1 , 0 ) ;
my @indices = ( 6 , 1 , 7 ) ;
disjointSort( \@values , @indices ) ;
print "[@values]\n" ;

Output:

[7 0 5 4 3 2 1 6]

## Perl 6

Works with: Rakudo version 2018.03

### Inline

Using L-value slice of the array, and `sort` as a mutating method:

my @values  = 7, 6, 5, 4, 3, 2, 1, 0;
my @indices = 6, 1, 7;

@values[ @indices.sort ] .= sort;

@values.perl.say;
Output:
[7, 0, 5, 4, 3, 2, 1, 6]

### Iterative

sub disjointSort( @values, @indices --> List ) {
my @sortedValues = @values[ @indices ].sort ;
for @indices.sort -> \$insert {
@values[ \$insert ] = @sortedValues.shift ;
}
return @values ;
}

my @values = ( 7 , 6 , 5 , 4 , 3 , 2 , 1 , 0 ) ;
my @indices = ( 6 , 1 , 7 ) ;
my @sortedValues = disjointSort( @values , @indices ) ;
@sortedValues.perl.say ;

Output:

[7, 0, 5, 4, 3, 2, 1, 6]

## Phix

Lightly modified copy of Euphoria

function uniq(sequence s)
integer last=s[1], this, ndx = 1
for i=2 to length(s) do
this = s[i]
if this!=last then
ndx += 1
s[ndx] = this
last = this
end if
end for
return s[1..ndx]
end function

function disjoint_sort(sequence s, sequence idx)
sequence copies
if length(idx)>1 then
idx = uniq(sort(idx))
copies = repeat(0, length(idx))
for i=1 to length(idx) do
copies[i] = s[idx[i]]
end for
copies = sort(copies)
for i=1 to length(idx) do
s[idx[i]] = copies[i]
end for
end if
return s
end function

?disjoint_sort({7,6,5,4,3,2,1,0},{7,2,8})
Output:
{7,0,5,4,3,2,1,6}

## PicoLisp

The indices are incremented here, as PicoLisp is 1-based

(let (Values (7 6 5 4 3 2 1 0)  Indices (7 2 8))
(mapc
'((V I) (set (nth Values I) V))
(sort (mapcar '((N) (get Values N)) Indices))
(sort Indices) )
Values )

Output:

-> (7 0 5 4 3 2 1 6)

## PowerShell

Works with: PowerShell version 4.0

function sublistsort(\$values, \$indices) {
\$indices = \$indices | sort
\$sub, \$i = (\$values[\$indices] | sort), 0
\$indices | foreach { \$values[\$_] = \$sub[\$i++] }
\$values
}
\$values = 7, 6, 5, 4, 3, 2, 1, 0
\$indices = 6, 1, 7
"\$(sublistsort \$values \$indices)"

Output:

7 0 5 4 3 2 1 6

## PureBasic

Based on the C implementation

Procedure Bubble_sort(Array idx(1), n, Array buf(1))
Protected i, j
SortArray(idx(),#PB_Sort_Ascending)
For i=0 To n
For j=i+1 To n
If buf(idx(j)) < buf(idx(i))
Swap buf(idx(j)), buf(idx(i))
EndIf
Next
Next
EndProcedure

Procedure main()
DataSection
values: Data.i 7, 6, 5, 4, 3, 2, 1, 0
indices:Data.i 6, 1, 7
EndDataSection

Dim values.i(7) :CopyMemory(?values, @values(), SizeOf(Integer)*8)
Dim indices.i(2):CopyMemory(?indices,@indices(),SizeOf(Integer)*3)

If OpenConsole()
Protected i
PrintN("Before sort:")
For i=0 To ArraySize(values())
Print(Str(values(i))+" ")
Next

PrintN(#CRLF\$+#CRLF\$+"After sort:")
Bubble_sort(indices(), ArraySize(indices()), values())
For i=0 To ArraySize(values())
Print(Str(values(i))+" ")
Next

Print(#CRLF\$+#CRLF\$+"Press ENTER to exit")
Input()
EndIf
EndProcedure

main()
Before sort:
7 6 5 4 3 2 1 0

After sort:
7 0 5 4 3 2 1 6

## Python

The function modifies the input data list in-place and follows the Python convention of returning None in such cases.

>>> def sort_disjoint_sublist(data, indices):
indices = sorted(indices)
values = sorted(data[i] for i in indices)
for index, value in zip(indices, values):
data[index] = value

>>> d = [7, 6, 5, 4, 3, 2, 1, 0]
>>> i = set([6, 1, 7])
>>> sort_disjoint_sublist(d, i)
>>> d
[7, 0, 5, 4, 3, 2, 1, 6]
>>> # Which could be more cryptically written as:
>>> def sort_disjoint_sublist(data, indices):
for index, value in zip(sorted(indices), sorted(data[i] for i in indices)): data[index] = value

>>>

Or, checking a dictionary for sublist indices, and returning a new (rather than mutated) list:

# disjointSort :: [Int] -> [Int] -> [Int]
def disjointSort(ixs):
def go(xs):
ks = sorted(ixs)
dct = dict(zip(ks, sorted(xs[k] for k in ks)))
return list(dct[i] if i in dct else x for i, x in enumerate(xs))
return lambda xs: go(xs)

print(
disjointSort([6, 1, 7])(
[7, 6, 5, 4, 3, 2, 1, 0]
)
)
Output:
[7, 0, 5, 4, 3, 2, 1, 6]

## R

R lets you access elements of vectors with a vector of indices.

values=c(7,6,5,4,3,2,1,0)
indices=c(7,2,8)
values[sort(indices)]=sort(values[indices])
print(values)

Output:

7 0 5 4 3 2 1 6

## Racket

#lang racket

(define (sort-disjoint l is)
(define xs
(sort (for/list ([x l] [i (in-naturals)] #:when (memq i is)) x) <))
(let loop ([l l] [i 0] [xs xs])
(cond [(null? l) l]
[(memq i is) (cons (car xs) (loop (cdr l) (add1 i) (cdr xs)))]
[else (cons (car l) (loop (cdr l) (add1 i) xs))])))

(sort-disjoint '(7 6 5 4 3 2 1 0) '(6 1 7))
;; --> '(7 0 5 4 3 2 1 6)

## REXX

Duplicate entries in the index list aren't destructive or illegal.

Note that the list may contain numbers in any form (integer, floating point, exponentationed),
as well as alphabetic/alphanumeric/non-displayable characters.

The REXX language normally uses a one-based index.

/*REXX program uses a   disjointed sublist   to  sort  a  random list  of values.       */
parse arg old ',' idx /*obtain the optional lists from the CL*/
if old='' then old= 7 6 5 4 3 2 1 0 /*Not specified: Then use the default.*/
if idx='' then idx= 7 2 8 /* " " " " " " */
say ' list of indices:' idx; say /* [↑] is for one─based lists. */
say ' unsorted list:' old /*display the old list of numbers. */
say ' sorted list:' disjoint_sort(old,idx) /*sort 1st list using 2nd list indices.*/
exit /*stick a fork in it, we're all done. */
/*──────────────────────────────────────────────────────────────────────────────────────*/
disjoint_sort: procedure; parse arg x,ix; y=; z=; p= 0
ix= sortL(ix) /*ensure the index list is sorted*/
do i=1 for words(ix) /*extract indexed values from X.*/
z= z word(x, word(ix, i) ) /*pick the correct value from X.*/
end /*j*/
z= sortL(z) /*sort extracted (indexed) values*/
do m=1 for words(x) /*re─build (re-populate) X list.*/
if wordpos(m, ix)==0 then y=y word(x,m) /*is the same or new?*/
else do; p= p + 1; y= y word(z, p)
end
end /*m*/
return strip(y)
/*──────────────────────────────────────────────────────────────────────────────────────*/
sortL: procedure; parse arg L; n= words(L); do j=1 for n; @.j= word(L,j)
end /*j*/
do k=1 for n-1 /*sort a list using a slow method*/
do m=k+1 to n; if @.m<@.k then parse value @.k @.m with @.m @.k
end /*m*/
end /*k*/ /* [↑] use PARSE for swapping.*/
\$= @.1; do j=2 to n; \$= \$ @.j
end /*j*/
return \$
output   when using the default inputs:
list of indices: 7 2 8

unsorted list: 7 6 5 4 3 2 1 0
sorted list: 7 0 5 4 3 2 1 6

## Ruby

By convention, the exlamation mark in the method name indicates that something potentially dangerous can happen. (In this case, the in place modification).

def sort_disjoint_sublist!(ar, indices)
values = ar.values_at(*indices).sort
indices.sort.zip(values).each{ |i,v| ar[i] = v }
ar
end

values = [7, 6, 5, 4, 3, 2, 1, 0]
indices = [6, 1, 7]
p sort_disjoint_sublist!(values, indices)

Output

[7, 0, 5, 4, 3, 2, 1, 6]

## Run BASIC

Normally we sort with SQLite in memory. Faster and less code

sortData\$ = "7, 6, 5, 4, 3, 2, 1, 0"
sortIdx\$ = "7, 2, 8"

numSort = 8
dim sortData(numSort)
for i = 1 to numSort
sortData(i) = val(word\$(sortData\$,i,","))
next i

while word\$(sortIdx\$,s + 1) <> ""
s = s + 1
idx = val(word\$(sortIdx\$,s))
gosub [bubbleSort]
wend
end

[bubbleSort]
sortSw = 1
while sortSw = 1
sortSw = 0
for i = idx to numSort - 1 ' start sorting at idx
if sortData(i) > sortData(i+1) then
sortSw = 1
sortHold = sortData(i)
sortData(i) = sortData(i+1)
sortData(i+1) = sortHold
end if
next i
wend
RETURN

## Scala

Library: Scala
import scala.compat.Platform

object SortedDisjointSubList extends App {
val (list, subListIndex) = (List(7, 6, 5, 4, 3, 2, 1, 0), List(6, 1, 7))

def sortSubList[T: Ordering](indexList: List[Int], list: List[T]) = {
val subListIndex = indexList.sorted
val sortedSubListMap = subListIndex.zip(subListIndex.map(list(_)).sorted).toMap

list.zipWithIndex.map { case (value, index) =>
if (sortedSubListMap.isDefinedAt(index)) sortedSubListMap(index) else value
}
}

assert(sortSubList(subListIndex, list) == List(7, 0, 5, 4, 3, 2, 1, 6), "Incorrect sort")
println(s"List in sorted order.\nSuccessfully completed without errors. [total \${Platform.currentTime - executionStart} ms]")
}

## Scheme

Works with: Gauche Scheme
(use gauche.sequence)
(define num-list '(7 6 5 4 3 2 1 0))
(define indices '(6 1 7))
(define table
(alist->hash-table
(map cons
(sort indices)
(sort indices < (lambda (x) (~ num-list x))))))

(map last
(sort
(map-with-index
(lambda (i x) (list (hash-table-get table i i) x))
num-list)
<
car))
Output:
(7 0 5 4 3 2 1 6)

## Sidef

func disjointSort(values, indices) {
values[indices.sort] = [values[indices]].sort...
}

var values = [7, 6, 5, 4, 3, 2, 1, 0];
var indices = [6, 1, 7];

disjointSort(values, indices);
say values;
Output:
[7, 0, 5, 4, 3, 2, 1, 6]

## Standard ML

Works with: SML/NJ
Translation of: Go
functor SortDisjointFn (A : MONO_ARRAY) : sig
val sort : (A.elem * A.elem -> order) -> (A.array * int array) -> unit
end = struct

structure DisjointView : MONO_ARRAY = struct
type elem = A.elem
type array = A.array * int array
fun length (a, s) = Array.length s
fun sub ((a, s), i) = A.sub (a, Array.sub (s, i))
fun update ((a, s), i, x) = A.update (a, Array.sub (s, i), x)

(* dummy implementations for not-needed functions *)
type vector = unit
val maxLen = Array.maxLen
fun array _ = raise Domain
fun fromList _ = raise Domain
fun tabulate _ = raise Domain
fun vector _ = raise Domain
fun copy _ = raise Domain
fun copyVec _ = raise Domain
fun appi _ = raise Domain
fun app _ = raise Domain
fun modifyi _ = raise Domain
fun modify _ = raise Domain
fun foldli _ = raise Domain
fun foldl _ = raise Domain
fun foldri _ = raise Domain
fun foldr _ = raise Domain
fun findi _ = raise Domain
fun find _ = raise Domain
fun exists _ = raise Domain
fun all _ = raise Domain
fun collate _ = raise Domain
end

structure DisjointViewSort = ArrayQSortFn (DisjointView)

fun sort cmp (arr, indices) = (
ArrayQSort.sort Int.compare indices;
DisjointViewSort.sort cmp (arr, indices)
)
end

Usage:

- structure IntArray = struct
=   open Array
=   type elem = int
=   type array = int Array.array
=   type vector = int Vector.vector
= end;
structure IntArray :
sig
[ ... rest omitted ]
- structure IntSortDisjoint = SortDisjointFn (IntArray);
structure IntSortDisjoint :
sig val sort : (A.elem * A.elem -> order) -> A.array * int array -> unit end
- val a = Array.fromList [7, 6, 5, 4, 3, 2, 1, 0];
val a = [|7,6,5,4,3,2,1,0|] : int array
- val indices = Array.fromList [6, 1, 7];
val indices = [|6,1,7|] : int array
- IntSortDisjoint.sort Int.compare (a, indices);
val it = () : unit
- a;
val it = [|7,0,5,4,3,2,1,6|] : int array

## Swift

Translation of: Go

Sorts an array "wrapper" which represents a "view" into the disjoint sublist of the array.

struct DisjointSublistView<T> : MutableCollectionType {
let array : UnsafeMutablePointer<T>
let indexes : [Int]

subscript (position: Int) -> T {
get {
return array[indexes[position]]
}
set {
array[indexes[position]] = newValue
}
}
var startIndex : Int { return 0 }
var endIndex : Int { return indexes.count }
func generate() -> IndexingGenerator<DisjointSublistView<T>> { return IndexingGenerator(self) }
}

func sortDisjointSublist<T : Comparable>(inout array: [T], indexes: [Int]) {
var d = DisjointSublistView(array: &array, indexes: sorted(indexes))
sort(&d)
}

var a = [7, 6, 5, 4, 3, 2, 1, 0]
let ind = [6, 1, 7]
sortDisjointSublist(&a, ind)
println(a)
Output:
[7, 0, 5, 4, 3, 2, 1, 6]

## Tcl

This returns the sorted copy of the list; this is idiomatic for Tcl programs where values are immutable.

package require Tcl 8.5
proc disjointSort {values indices args} {
# Ensure that we have a unique list of integers, in order
# We assume there are no end-relative indices
set indices [lsort -integer -unique \$indices]
# Map from those indices to the values to sort
set selected {}
foreach i \$indices {lappend selected [lindex \$values \$i]}
# Sort the values (using any extra options) and write back to the list
foreach i \$indices v [lsort {*}\$args \$selected] {
lset values \$i \$v
}
# The updated list is the result
return \$values
}

Demonstration:

set values {7 6 5 4 3 2 1 0}
set indices {6 1 7}
puts \[[join [disjointSort \$values \$indices] ", "]\]

Output:

[7, 0, 5, 4, 3, 2, 1, 6]

## TUSCRIPT

TUSCRIPT indexing is one based

\$\$ MODE TUSCRIPT
values="7'6'5'4'3'2'1'0"
indices="7'2'8"
v_unsorted=SELECT (values,#indices)
v_sort=DIGIT_SORT (v_unsorted)
i_sort=DIGIT_SORT (indices)
LOOP i=i_sort,v=v_sort
values=REPLACE (values,#i,v)
ENDLOOP
PRINT values

Output:

7'0'5'4'3'2'1'6

## Ursala

#import std
#import nat

disjoint_sort = ^|(~&,num); ("i","v"). (-:(-:)"v"@p nleq-<~~lSrSX ~&rlPlw~|/"i" "v")*lS "v"

#cast %nL

t = disjoint_sort({6,1,7},<7,6,5,4,3,2,1,0>)

output:

<7,0,5,4,3,2,1,6>

## zkl

values :=T(7, 6, 5, 4, 3, 2, 1, 0);
indices:=T(6, 1, 7);

indices.apply(values.get).sort() // a.get(0) == a[0]
.zip(indices.sort()) //-->(v,i) == L(L(0,1),L(1,6),L(6,7))
.reduce(fcn(newList,[(v,i)]){ newList[i]=v; newList },values.copy())
.println(); // new list

This is an create-new-object version. An in place version is almost identical:

values :=L(7, 6, 5, 4, 3, 2, 1, 0);

indices.apply(values.get).sort() // a.get(0) == a[0]
.zip(indices.sort()) //-->(v,i) == L(L(0,1),L(1,6),L(6,7))
.apply2(fcn([(v,i)],list){ list[i]=v },values);

values.println(); // modified list
Output:
L(7,0,5,4,3,2,1,6)