Loading problem…
You are given an array of integers stones where stones[i] is the weight of the i-th stone. We are playing a game with the stones. On each turn, we choose the heaviest two stones and smash them together. Suppose the heaviest two stones have weights x and y with x <= y. The result of this smash is: - If x == y, both stones are destroyed, and - If x != y, the stone of weight x is destroyed, and the stone of weight y has new weight y - x. At the end of the game, there is at most one stone left. Return the weight of the last remaining stone. If there are no stones left, return 0.
Example 1
Input: stones = [2,7,4,1,8,1]
Output: 1
Explanation: Smash 8 and 7 → 1, leaving [2,4,1,1,1]. Smash 4 and 2 → 2, leaving [2,1,1,1]. Smash 2 and 1 → 1, leaving [1,1,1]. Smash 1 and 1 → both destroyed, leaving [1].
Example 2
Input: stones = [1]
Output: 1
Explanation: There is only one stone, so it is never smashed and its weight 1 is returned.
Example 3
Input: stones = [3,3]
Output: 0
Explanation: The two stones weigh the same, so both are destroyed and nothing is left.
Each turn needs the two heaviest stones. A max-heap gives them in O(log n) and lets us push the smashed remainder back just as cheaply.
Run checks all cases above. Submit evaluates all test cases.