Problem: Last Stone Weight

Statement

You are given an integer array stones, where each element stones[i] represents the weight of the $i^{th}$ stone.

A game is played with these stones. In each turn, the two heaviest stones are selected and smashed together. Let the weights of these two stones be x and y, where x $\leq$ y. The outcome of the smash is as follows:

• If x $=$ y, both stones are completely destroyed.

• If x $\neq$ y, the stone of weight x is destroyed, and the stone of weight y is reduced to a new weight of y $-$ ...