# Input/Output for pairs of numbers

Input/Output for pairs of numbers is a draft programming task. It is not yet considered ready to be promoted as a complete task, for reasons that should be found in its talk page.

From lines of input starting with a line containing the numbers of pairs to follows, followed by that number of pairs of integers separated by a space on separate lines from STDIN, output the sum of each pair to STDOUT.

Sample input with corresponding output

Input

```5
1 2
10 20
-3 5
100 2
5 5```

Output

```3
30
2
102
10```

## 11l

Translation of: Python
```F do_stuff(a, b)
R a + b

V t = Int(input())
L 1..t
V (a, b) = input().split(‘ ’).map(Int)
print(do_stuff(a, b))```

## Action!

```INT FUNC CalcSum(CHAR ARRAY s)
INT sum,i
CHAR ARRAY tmp(100)

sum=ValI(s)
FOR i=1 TO s(0)
DO
IF s(i)=32 THEN EXIT FI
OD
SCopyS(tmp,s,i,s(0))
sum==+ValI(tmp)
RETURN (sum)

PROC Main()
BYTE i,nLines
INT ARRAY sums(256)
CHAR ARRAY line(256)

nLines=InputB()
IF nLines=0 THEN RETURN FI

FOR i=0 TO nLines-1
DO
InputS(line)
sums(i)=CalcSum(line)
OD

PutE()
FOR i=0 TO nLines-1
DO
PrintIE(sums(i))
OD
RETURN```
Output:
```5
1 2
10 20
-3 5
100 2
5 5

3
30
2
102
10
```

There can be newlines before or between numbers. The pairs may be on separate lines or the same line.

```with Ada.Text_IO;         use Ada.Text_IO;

procedure Main is
count  : Integer;
First  : Integer;
Second : Integer;
begin
Get (count);
for I in 1 .. count loop
Get (First);
Get (Second);
Put (Item => First + Second, Width => 1);
New_Line;
end loop;
end Main;
```
Output:

Output using the example input:

```3
30
2
102
10
```

## ALGOL 68

Simple version - there can be newlines before or between the numbers

```# read a number from stand in then read and add that many pairs of numbers from stand in      #
# and write the sum to stand out. If non integer data is supplied, a runtime error will occur #
TO ( INT n; read( ( n, newline ) ); n ) DO
INT a, b;
read( ( a, b, newline ) );
print( ( a + b, newline ) )
OD```

Strict version - the pairs of numbers must appear on the same line.

```# read a number from stand in then read and add that many pairs of numbers from stand in      #
# and write the sum to stand out. If non integer data is supplied, a runtime error will occur #
# This version does not allow the pairs of numbers to be spread over several lines            #
STRING line;
FILE   numbers;
associate( numbers, line );
TO ( INT n
; read( ( line, newline ) )
; reset( numbers )
; get( numbers, ( n ) )
; n
)
DO
INT a, b;
read( ( line, newline ) );
reset( numbers );
get( numbers, ( a, b ) );
print( ( a + b, newline ) )
OD```
Output:
```         +3
+30
+2
+102
+10
```

## Applesoft BASIC

``` 100  GOSUB 230"INPUT LINE"
110  LET N =  VAL (L\$) - 1
120  IF N < 0 THEN  END
130  DIM SUM(N)
140  FOR I = 0 TO N
150      GOSUB 330"SUM PAIR FROM INPUT LINE"
160      LET SUM(I) = S
170  NEXT I
190  FOR I = 0 TO N
200      PRINT SUM(I)
210  NEXT
220  END

230  LET L\$ = ""
240  LET C\$ = ""
250  FOR C = 0 TO 1 STEP 0
260      LET L\$ = L\$ + C\$
270      GET C\$
280      PRINT  CHR\$ (0)C\$;
290      LET C = C\$ =  CHR\$ (13)
300  NEXT C
310  LET C =  FRE (0)
320  RETURN

330  GOSUB 230"INPUT LINE"
340  FOR C = 1 TO LEN(L\$)
350      IF MID\$(L\$, C, 1) <> " " THEN NEXT C
360  S = VAL(MID\$(L\$, 1, C - 1)) + VAL(MID\$(L\$, C + 1))
370  RETURN
```

Input

```5
1 2
10 20
-3 5
100 2
5 5
```
Output:
```3
30
2
102
10
```

## AWK

```NR == 1 {n=\$1; next}
NR > n+1 {exit}
{print \$1+\$2}
```

## Batch File

```@echo off
setlocal enabledelayedexpansion

set /p pairs=

for /l %%i in (1,1,%pairs%) do set /p pair%%i=
for /l %%i in (1,1,%pairs%) do (
for %%j in (!pair%%i!) do (
set /a sum%%i+=%%j
)
)

for /l %%i in (1,1,%pairs%) do echo !sum%%i!
pause>nul
```
Input:
```5
10 10
5 6
-3 2
-6 -8
111 2
```
Output:
```20
11
-1
-14
113
```

## BBC BASIC

The specification is a bit ambiguous, but I understood it as wanting us to read all the numbers in first and then print all the sums. This program does that. It could be a couple of lines shorter if we were allowed to use a comma instead of a space as separator.

```INPUT n%
DIM pairs%(n% - 1, 1)
FOR i% = 0 TO n% - 1
INPUT s\$
pairs%(i%, 0) = VAL(LEFT\$(s\$, INSTR(s\$, " ")))
pairs%(i%, 1) = VAL(MID\$(s\$, INSTR(s\$, " ")))
NEXT
FOR i% = 0 TO n% - 1
PRINT pairs%(i%, 0) + pairs%(i%, 1)
NEXT
```

With the sample inputs:

```?5
?1 2
?10 20
?-3 5
?100 2
?5 5
3
30
2
102
10```

## C

```#include <stdio.h>
#include <stdlib.h>

int main(void)
{
int i, n, a, b, *f;
scanf("%d", &n);
f = malloc(sizeof(*f) * n);

for (i = 0; i < n; i++) {
if (2 != scanf("%d %d", &a, &b))
abort();
f[i] = a + b;
}

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

return 0;
}
```

Output for example input

```3
30
2
102
10
```

## C#

```using System;
using static System.Linq.Enumerable;

public class Program
{
static void Main(string[] args)
{
for (int line = 0; line < count; line++) {
}
}
}
```
Output:
```3
30
2
102
10
```

## C++

```#include <iostream>
#include <vector>
using namespace std;

int doStuff(int a, int b) {
return a + b;
}

int main() {

int t;
cin >> t;

vector<pair<int, int>> list(t);

for(int j=0; j<t; j++){
cin >> list[j].first >> list[j].second;
}

cout << endl;

for(int j=0;j<t;j++){
cout << doStuff(list[j].first, list[j].second) << endl;;
}
}
```

Run as per given input

```5
1 2
10 20
-3 5
100 2
5 5

3
30
2
102
10
```

## D

This works with any number of integers on lines.

```void main() {
import std.stdio, std.string, std.conv, std.algorithm;

foreach (immutable _; 0 .. readln.strip.to!uint)
}
```

## Factor

```USING: io math.parser prettyprint sequences splitting ;
IN: rosetta-code.pair-output

: process-line ( str -- n )
" " split [ string>number ] map-sum ;
: main ( -- ) lines 1 tail [ process-line ] map [ . ] each ;

MAIN: main
```
Output:
```3
30
2
102
10
```

## Fortran

Works with: Fortran version 95 and later
```program i_o_pairs
implicit none

integer :: npairs
integer :: i
integer, allocatable :: pairs(:,:)

allocate(pairs(npairs,2))

do i = 1, npairs
end do
write(*, "(i0)") sum(pairs, 2)

end program
```

## FreeBASIC

```' FB 1.05.0 Win64

Dim As UInteger n
Dim As Integer x, y
Input "", n
Dim sums(1 To n) As Integer
For i As Integer = 1 To  n
Input "", x, y
sums(i) =  x + y
Next
Print
For i As Integer = 1 To n
Print Str(sums(i))
Next
Sleep
```
Output:
```5
1 2
10 20
-3 5
100 2
5 5

3
30
2
102
10
```

See Pascal

## Go

```package main

import (
"fmt"
"log"
)

func main() {
var lines int
n, err := fmt.Scanln(&lines)
if n != 1 || err != nil {
log.Fatal(err)
}

var a, b int
for ; lines > 0; lines-- {
n, err = fmt.Scanln(&a, &b)
if n != 2 || err != nil {
log.Fatal(err)
}
fmt.Println(a + b)
}
}
```

This solution will actually add any number of integers placed on each line. Additionally, after removing the bits of code that cut out the specified number of lines, the solution will sum any number of lines of integers.

```main = do
contents <- getContents
nums  =  map (map read.words).take numberOfLines.tail.lines\$ contents
sums  =  map sum nums
mapM_ print sums
```

## J

```\$ cat <<EOF | jconsole -js '([: exit 0: [: smoutput [: ,. [: ({. {. }.) [: (+/"1) [: (0&".;._2) (1!:1)) 3'
> 5
> 1 2
> 10 20
> -3 5
> 100 2
> 5 5
> EOF
3
30
2
102
10
```

Considerably simpler than [explanation] output for lines of text, this sentence is a single fork. J pads the numeric arrays of 0&".;._2 (numbers cut) with 0 . We form the +/"1 (row sums), then take the sum of the first row of the beheaded sums ({. {. }.) for display. ,. (raveled items) reshapes the vector into a column-vector shaped matrix. And the [: (cap) causes the monadic form of the verb to cap's right.

## Java

```import java.util.Scanner;

public class Main {

public static int doStuff(int a, int b){
int sum = a+b;
return sum;
}

public static void main(String[] args) {
Scanner in = new Scanner(System.in);

int n = in.nextInt();
for(int i=0; i<n; i++){
int a = in.nextInt();
int b= in.nextInt();
int result = doStuff(a, b);
System.out.println(result);
}
}
}
```

## jq

Works with: jq

Works with gojq, the Go implementation of jq

The solution below assumes the input is in a file named input.txt, and is quite lenient about the presentation of the numbers. For example, it does not require that each pair of numbers be presented on the same line.

```< input.txt jq -n '
input as \$n
| if \$n | (type != "number" or . < 0)
then "Number of pairs must be non-negative." | error
else range(0; \$n)
end'
```
Output:
```3
30
2
102
10
```

## Julia

```parseints() = (a = split(strip(readline()), r"\s+"); map(x -> parse(Int, x), a))

const lines = parseints()

for _ in 1:lines
println(sum(parseints()))
end
```
Output:
```3
5 6
11
8 2
10
9 23
32
```

## Kotlin

```// version 1.0.6

import java.util.Scanner

fun main(args: Array<String>) {
val sc = Scanner(System.`in`)  // note: backticks required as 'in' is a Kotlin keyword
val n = sc.nextInt()
val x = IntArray(n)
val y = IntArray(n)
for (i in 0 until n) {
x[i] = sc.nextInt()
y[i] = sc.nextInt()
}
println()
for (i in 0 until n) println(x[i] + y[i])
}
```

Sample input/output:

Output:
```5
1 2
10 20
-3 5
100 2
5 5

3
30
2
102
10
```

## Lua

This solution will sum any number of space-separated numbers per input line, assuming the user won't input too many to store in the available RAM.

```local intTab, numLines, sum = {}, io.read()
for i = 1, numLines do
sum = 0
for number in io.read():gmatch("%S+") do sum = sum + number end
table.insert(intTab, sum)
end
for _, result in pairs(intTab) do print(result) end
```

## Nim

```import sequtils, strutils

for _ in 1..lineCount:
let fields = line.splitWhitespace()
assert fields.len == 2
let pair = fields.map(parseInt)
echo pair + pair
```
Output:

For the sample input:

```3
30
2
102
10```

## OCaml

```let () =
let n = int_of_string (input_line stdin) in
for i = 1 to n do
let line = input_line stdin in
match String.split_on_char ' ' line with
| a::b::[] ->
let x = int_of_string a + int_of_string b in
print_int x;
print_newline ()
| _ ->
raise (Invalid_argument "wrong input")
done
```
Output:
```\$ cat input.txt
5
1 2
10 20
-3 5
100 2
5 5
\$ cat input.txt | ocaml pairs.ml
3
30
2
102
10
```

## PARI/GP

Interestingly, this task is not possible to implement directly in GP, since `input()`, like the gp REPL itself, ignores spaces. One must use PARI:

```#include <stdio.h>
#include <stdlib.h>
#include <pari/pari.h>

int main(void);

int
main()
{
int i, n, a, b;
GEN f, sum;
pari_sp ltop;

// 1 MB stack, not using prime table
pari_init(1000000, 0);

scanf("%d", &n);
GEN f = cgetg(n+1, t_VEC);

for (i = 1; i <= n; i++) {
if (2 != scanf("%d %d", &a, &b)) abort();

ltop = avma;

// Add a and b in PARI

// Store the sum in a vector, collecting garbage as you go.
gel(f, i) = gerepileupto(ltop, sum);
}

pari_printf("%Ps", f);
return 0;
}
```

Of course for such a simple task this has very little advantage over C, but it does demonstrate the general principle.

## Pascal

```program inputOutputForPairsOfNumbers(input, output);
var
lines: integer;
x: integer;
y: integer;
begin
for lines := 1 to lines do
begin
writeLn(x + y)
end
end.
```
Output:
```          3
30
2
102
10
```

## Perl

```\$n = scalar <>;

for (1..\$n) {
(\$a,\$b) = split ' ', <>;
print \$a + \$b . "\n";
}
```

## Phix

```without js -- (file i/o)
string line = gets(0)
sequence r = scanf(trim(line),"%d"), s = {}
if length(r)!=1 then
crash("input not a number")
end if
puts(1,"\n")
for i=1 to r do
line = gets(0)
r = scanf(trim(line),"%d %d")
if length(r)!=1 then
crash("input not a pair of numbers")
end if
s &= sum(r)
puts(1,"\n")
end for
puts(1,"===\n")
pp(s)
```
Output:

(or more accurately the final state of the console)

```5
1 2
10 20
-3 5
100 2
5 5
===
{3,30,2,102,10}
```

### avoiding file i/o

And hence runnable in a browser, as well as on the desktop.
User input would need to be a proper GUI rather than a console prompt, perhaps like Arithmetic/Integer#Phix or the much prettier/more polished Morse_code#Phix.

```with javascript_semantics
sequence lines = split("""
5
1 2
10 20
-3 5
100 2
5 5""","\n")
string line = lines
sequence r = scanf(trim(line),"%d"), s = {}
if length(r)!=1 then
crash("input not a number")
end if
puts(1,"\n")
for i=1 to r do
line = lines[i+1]
r = scanf(trim(line),"%d %d")
if length(r)!=1 then
crash("input not a pair of numbers")
end if
s &= sum(r)
end for
pp(s)
```

Output same as the last line of the above.

## PowerShell

```# script.ps1

\$in, \$line = (Get-Content \$args), 0
\$nb = \$in[\$line++]
1..\$nb | foreach {
\$sum = 0
\$in[\$line++].Split() | foreach{ \$sum += \$_}
\$sum
}

# ./script file.txt
```

## Python

```def do_stuff(a, b):
return a + b

t = input()
for x in range(0, t):
a, b = raw_input().strip().split()
print do_stuff(int(a), int(b))
```

### Python: Alternative

Or without the function do_stuff() and that works for Python 3 and Python 2:

```>>> try: raw_input
except NameError: raw_input = input

>>> for i in range(int(raw_input())):
print(sum(int(numberstring)
for numberstring
in raw_input().strip().split()))

5
1 2
3
10 20
30
-3 5
2
100 2
102
5 5
10
>>>
```

(All but the first line of single numbers, (the 5), is output from the program).

### Python: With prompts

More than is asked for by the task, but if working interactively then the following version adds prompts.

```>>> for i in range(int(raw_input('lines: '))):
print(sum(int(numberstring)
for numberstring in raw_input('two numbers: ').strip().split()))

lines: 5
two numbers: 1 2
3
two numbers: 10 20
30
two numbers: -3 5
2
two numbers: 100 2
102
two numbers: 5 5
10
>>>
```

## Racket

```#lang racket
;(for ([i (in-range line-number)])

(define line-count (string->number ;only reads numbers

(for ([i (in-range line-count)])
(displayln (apply +
(map string->number
```

## Raku

(formerly Perl 6)

```for ^get() { say [+] get.words }
```

This does more than the task asks. It will sum as many numbers as you care to put on each line, and the numbers need not be integers, but may also be a mix of rational, floating-point, or complex numbers. More subtly, get can read from a file specified as a command-line argument, but defaults to taking STDIN if no filename is specified.

## REXX

This version isn't limited to summing integers, any form of number that REXX supports can be used.

```/*REXX pgm reads a number (from the CL), reads that number of pairs, & writes their sum.*/
/*all input is from the  Command Line. */
\$=linein()                                  /*read a line (a record) from the C.L. */
say word(\$, 1)   +   word(\$, 2)             /*display the sum of a pair of numbers.*/
end   /*linein() */
/*stick a fork in it,  we're all done. */
```

## Ring

```# Project : Input/Output for Pairs of Numbers

pairs = ["5", "1 2", "10 20", "-3 5", "100 2", "5 5"]
for n = 1 to len(pairs)
nr = 0
for p = 1 to len(pairs[n])
if substr(pairs[n], p, 1) = " "
nr = p
ok
next
if nr > 0
n1 = number(left(pairs[n], nr - 1))
n2 = number(right(pairs[n], len(pairs[n]) - nr + 1))
n3 = n1 + n2
see n3 + nl
ok
next```

Output:

```3
30
2
102
10
```

### Ring: Alternative

```# Project : Input/Output for Pairs of Numbers (Alternative)

pairs = ["5", "1 2", "10 20", "5 -3", "100 2", "5 5"]
for n = 1 to len(pairs)
nr = 0
for p = 1 to len(pairs[n])
if substr(pairs[n], p, 1) = " "
pairs[n] = substr(pairs[n], " ", "+")
nr = p
ok
next
if nr > 0
eval("ev = " + pairs[n])
see ev + nl
ok
next
>>>```
```3
30
2
102
10
```

## Ruby

```n = gets.to_i
n.times do
a, b = gets.split.map(&:to_i)
puts a + b
end
```

## Scala

```object IOPairs extends App {
private val in = scala.io.StdIn

for (_ <- 0 until n) {
val Array(a, b) = in.readLine().split(" ").map(_.toInt)

def doStuff(a: Long, b: Long): Long = a + b

println(doStuff(a, b))
}

}
```

## Tcl

```gets stdin n
while {\$n > 0} {
if {[scan [gets stdin] "%d %d" a b] == 2} {
puts [expr {\$a + \$b}]
}
incr n -1
}
```

## UNIX Shell

Works with: Bourne Again SHell
```read n
while (( n > 0 )); do
echo \$((a+b))
((n--))
done
```

## Ursa

```decl int amount
set amount (in int console)

decl int<> ints
for (decl int i) (< i amount) (inc i)
decl string input
set input (in string console)
append (int (split input " ")<0>) (int (split input " ")<1>) ints
end for

out endl console

for (set i 0) (< i (size ints)) (set i (int (+ 2 i)))
out (int (+ ints<i> ints<(int (+ i 1))>)) endl console
end for```

Networked version. Runs on port 20000.

```decl serverport sp
decl port p
sp.attach 20000
set p (sp.getconn)

decl int amount
set amount (in int p)

decl int<> ints
for (decl int i) (< i amount) (inc i)
decl string input
set input (in string p)
append (int (split input " ")<0>) (int (split input " ")<1>) ints
end for

out endl p

for (set i 0) (< i (size ints)) (set i (int (+ 2 i)))
out (int (+ ints<i> ints<(int (+ i 1))>)) endl p
end for```

## Wren

This assumes that both Stdin and Stdout are connected to a terminal.

```import "io" for Stdin

var output = Fn.new { |pairs| pairs.each { |p| System.print(p + p) } }

if (!n || !n.isInteger || n < 1) Fiber.abort("Number of pairs must be a positive integer.")
var pairs = []
for (i in 0...n) {
var sp = line.split(" ")
if (sp.count != 2) Fiber.abort("Each line must contain 2 integers, separated by a space.")
var p1 = Num.fromString(sp)
if (!p1 || !p1.isInteger) Fiber.abort("First value is not an integer.")
var p2 = Num.fromString(sp)
if (!p2 || !p2.isInteger) Fiber.abort("Second value is not an integer.")
}
System.print()
output.call(pairs)
```
Output:

Sample input/output:

```5
1 2
10 20
-3 5
100 2
5 5

3
30
2
102
10
```

## XPL0

The input file must be redirected on the command line, for example: iopair <iopair.txt

```int N;
for N:= 1 to IntIn(1) do
[IntOut(0, IntIn(1) + IntIn(1));
CrLf(0);
]```
Output:
```3
30
2
102
10
```

## zkl

Using the console as the input stream:

```fcn pairs{
}```
Output:
```pairs()
num pairs: 5
1 pair: 1 2
3
1 pair: 10 20
30
1 pair: -3 5
2
1 pair: 100 2
102
1 pair: 5 5
10
```