Last list item
List = [6, 81, 243, 14, 25, 49, 123, 69, 11]
Find two smallest items, summarize them, add to the end of list and delete them.
Repeat it until list contains one element.
Use unsorted list in output.
Show the steps and last item on this page.
Last list item 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.
- Task
C
<lang c>#include <stdio.h>
- include <stdlib.h>
int compare(const void *a, const void *b) {
int aa = *(const int *)a; int bb = *(const int *)b; if (aa < bb) return -1; if (aa > bb) return 1; return 0;
}
int main() {
int a[] = {6, 81, 243, 14, 25, 49, 123, 69, 11}; int isize = sizeof(int); int asize = sizeof(a) / isize; int i, sum; while (asize > 1) { qsort(a, asize, isize, compare); printf("Sorted list: "); for (i = 0; i < asize; ++i) printf("%d ", a[i]); printf("\n"); sum = a[0] + a[1]; printf("Two smallest: %d + %d = %d\n", a[0], a[1], sum); for (i = 2; i < asize; ++i) a[i-2] = a[i]; a[asize - 2] = sum; asize--; } printf("Last item is %d.\n", a[0]); return 0;
}</lang>
- Output:
Sorted list: 6 11 14 25 49 69 81 123 243 Two smallest: 6 + 11 = 17 Sorted list: 14 17 25 49 69 81 123 243 Two smallest: 14 + 17 = 31 Sorted list: 25 31 49 69 81 123 243 Two smallest: 25 + 31 = 56 Sorted list: 49 56 69 81 123 243 Two smallest: 49 + 56 = 105 Sorted list: 69 81 105 123 243 Two smallest: 69 + 81 = 150 Sorted list: 105 123 150 243 Two smallest: 105 + 123 = 228 Sorted list: 150 228 243 Two smallest: 150 + 228 = 378 Sorted list: 243 378 Two smallest: 243 + 378 = 621 Last item is 621.
Go
<lang go>package main
import (
"fmt" "sort"
)
func main() {
a := []int{6, 81, 243, 14, 25, 49, 123, 69, 11} for len(a) > 1 { sort.Ints(a) fmt.Println("Sorted list:", a) sum := a[0] + a[1] fmt.Printf("Two smallest: %d + %d = %d\n", a[0], a[1], sum) a = append(a, a[0]+a[1]) a = a[2:] } fmt.Println("Last item is", a[0], "\b.")
}</lang>
- Output:
Sorted list: [6 11 14 25 49 69 81 123 243] Two smallest: 6 + 11 = 17 Sorted list: [14 17 25 49 69 81 123 243] Two smallest: 14 + 17 = 31 Sorted list: [25 31 49 69 81 123 243] Two smallest: 25 + 31 = 56 Sorted list: [49 56 69 81 123 243] Two smallest: 49 + 56 = 105 Sorted list: [69 81 105 123 243] Two smallest: 69 + 81 = 150 Sorted list: [105 123 150 243] Two smallest: 105 + 123 = 228 Sorted list: [150 228 243] Two smallest: 150 + 228 = 378 Sorted list: [243 378] Two smallest: 243 + 378 = 621 Last item is 621.
Ring
<lang ring> see "working..." + nl
List = [6,81,243,14,25,49,123,69,11] Temp = [] n = 0 while true
n++ Temp = sort(List) first = Temp[1] second = Temp[2] ind1 = find(List,first) ind2 = find(List,second) if ind1 < ind2 del(List,ind2) del(List,ind1) else del(List,ind1) del(List,ind2) ok sum = first + second add(List,sum) if len(List) = 1 exit ok if n = 1 see nl + "List = " showArray(List) see nl ok showList(first,second,sum,List)
end
see "Last item is: " +List[1] + nl see "done..." + nl
func showList(first,second,sum,List)
see "two smallest is = " + first + " + " + second + " = " + sum + nl see "List = " showArray(List)
func showArray(array)
txt = "" see "[" for n = 1 to len(array) txt = txt + array[n] + "," next txt = left(txt,len(txt)-1) txt = txt + "]" see txt + nl
</lang>
- Output:
working... List = [81,243,14,25,49,123,69,17] two smallest is = 6 + 11 = 17 List = [81,243,14,25,49,123,69,17] two smallest is = 14 + 17 = 31 List = [81,243,25,49,123,69,31] two smallest is = 25 + 31 = 56 List = [81,243,49,123,69,56] two smallest is = 49 + 56 = 105 List = [81,243,123,69,105] two smallest is = 69 + 81 = 150 List = [243,123,105,150] two smallest is = 105 + 123 = 228 List = [243,150,228] two smallest is = 150 + 228 = 378 List = [243,378] Last item is: 621 done...
Wren
<lang ecmascript>var a = [6, 81, 243, 14, 25, 49, 123, 69, 11]
while (a.count > 1) {
a.sort() System.print("Sorted list: %(a)") var sum = a[0] + a[1] System.print("Two smallest: %(a[0]) + %(a[1]) = %(sum)") a.add(sum) a = a[2..-1]
}
System.print("Last item is %(a[0]).")</lang>
- Output:
Sorted list: [6, 11, 14, 25, 49, 69, 81, 123, 243] Two smallest: 6 + 11 = 17 Sorted list: [14, 17, 25, 49, 69, 81, 123, 243] Two smallest: 14 + 17 = 31 Sorted list: [25, 31, 49, 69, 81, 123, 243] Two smallest: 25 + 31 = 56 Sorted list: [49, 56, 69, 81, 123, 243] Two smallest: 49 + 56 = 105 Sorted list: [69, 81, 105, 123, 243] Two smallest: 69 + 81 = 150 Sorted list: [105, 123, 150, 243] Two smallest: 105 + 123 = 228 Sorted list: [150, 228, 243] Two smallest: 150 + 228 = 378 Sorted list: [243, 378] Two smallest: 243 + 378 = 621 Last item is 621.