Booj Code Test

Fun times with equilibrium indexes on an array.

What is an equilibrium index?

An equilibrium index of a sequence is an index into the sequence such that the sum of elements at lower indices is equal to the sum of elements at higher indices.

Instructions

Write a function that, given a sequence, returns its equilibrium indices (if any). Assume that the sequence may be very long. Feel free to Google for hints, but give lots of comments about what your thoughts are and your process for devising an algorithm.

Running the Test

phpunit EquilibriumIndexTest.php