not strictly a perl-specific query, i'm afraid, but can anyone help me with an algorithm:

i've got a variable length array of numbers, and i need to mark which combinations of them add up to zero

eg say the array (which is zero-based) is

-25, 14, 50, 20, -7, -8, -10

then elements 0, 2, 4, 5 & 6 add up to zero, but no other combinations do (except the same thing in a different order, which i don't want to count again).

how do i structure my loops so that it tests every possible permutation?

In reply to permutation algorithm by Basilides

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