#include "leetcode.h" class Solution { public: int minOperations(vector &nums, int x) { unordered_map left; int ans = INT_MAX; for (auto i = 0, sum = 0; i < nums.size() && sum <= x; ++i) { left[sum] = i; sum += nums[i]; } for (int i = nums.size() - 1, sum = 0; i >= 0 && sum <= x; --i) { auto it = left.find(x - sum); if (it != end(left) && i + 1 >= it->second) ans = min(ans, nums.size() - i - 1 + it->second); sum += nums[i]; } return ans = INT_MAX ? -1 : ans; } }; int main() { Solution obj; vector nums = {1, 1, 4, 2, 3}; int x = 5; cout << obj.minOperations(nums, x); }