Replacing nested loops foreach using map/each/etc

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On Monday, 25 May 2015 at 15:46:54 UTC, Dennis Ritchie wrote:
> On Monday, 25 May 2015 at 15:06:45 UTC, Alex Parrill wrote:
>> Hint: Use `cartesianProduct` [1] with three iota ranges to 
>> replace the foreachs, and `filter` to replace the if
>>
>> [1] 
>> http://dlang.org/phobos/std_algorithm_setops.html#.cartesianProduct
>
> Thank you. Is it possible to replace the loop `foreach` 
> function `each` or `chunkBy` with the auxiliary functions?
>
> import std.stdio, std.algorithm, std.range;
>
> void main() {
>
>     const x = 12, y = 65, z = 50, s = 1435;
>
>     auto a = iota(0, x + 1);
>
>     foreach (idx; cartesianProduct(a, a, a).filter!(i => i[0] * 
> (y + 3 * z) + i[1] * (y + 2 * z) + i[2] * (y + z) == s)) {
>         writeln(idx[0] + idx[1] + idx[2]);
>         writeln(idx[0] * 3 + idx[1] * 2 + idx[2]);
>         writeln(idx[0] * 3 + idx[1] * 2 + idx[2]);
>         writeln(idx[0], idx[1], idx[2]);
>     }
> }
> -----
> http://rextester.com/HZP96719

import std.algorithm;
import std.range;
import std.stdio;

void main()
{
     const x = 12, y = 65, z = 50, s = 1435;
     auto a = iota(0, x + 1);
     cartesianProduct(a, a, a)
       	.filter!(i => i[0] * (y + 3 * z)
             + i[1] * (y + 2 * z)
             + i[2] * (y + z)
             == s)
       	.each!((idx)
         {
             writeln(idx[0] + idx[1] + idx[2]);
             writeln(idx[0] * 3 + idx[1] * 2 + idx[2]);
             writeln(idx[0] * 3 + idx[1] * 2 + idx[2]);
             writeln(idx[0], idx[1], idx[2]);
         });
}