- Difficulty: Medium
- Tags: LeetCode, Medium, Array, Dynamic Programming, leetcode-1049, O(2^n)
Problem
You are given an array of integers stones
where stones[i]
is the weight of the ith
stone.
We are playing a game with the stones. On each turn, we choose any two stones and smash them together. Suppose the 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 weightx
is destroyed, and the stone of weighty
has new weighty - x
.
At the end of the game, there is at most one stone left.
Return the smallest possible weight of the left stone. If there are no stones left, return 0
.
Example 1:
Input: stones = [2,7,4,1,8,1] Output: 1 Explanation: We can combine 2 and 4 to get 2, so the array converts to [2,7,1,8,1] then, we can combine 7 and 8 to get 1, so the array converts to [2,1,1,1] then, we can combine 2 and 1 to get 1, so the array converts to [1,1,1] then, we can combine 1 and 1 to get 0, so the array converts to [1], then that's the optimal value.
Example 2:
Input: stones = [31,26,33,21,40] Output: 5
Constraints:
1 <= stones.length <= 30
1 <= stones[i] <= 100