Description
Minimum Operations to Reduce X to Zero
MediumYou are given an integer array nums and an integer x. In one operation, you can either remove the leftmost or the rightmost element from the array nums and subtract its value from x. Note that this modifies the array for future operations.
Return the minimum number of operations to reduce x to exactly 0 if it is possible, otherwise, return -1.
Example 1:
Input: nums = [1,1,4,2,3], x = 5 Output: 2 Explanation: The optimal solution is to remove the last two elements to reduce x to zero.
Example 2:
Input: nums = [5,6,7,8,9], x = 4 Output: -1
Example 3:
Input: nums = [3,2,20,1,1,3], x = 10 Output: 5 Explanation: The optimal solution is to remove the last three elements and the first two elements (5 operations in total) to reduce x to zero.
Constraints:
1 <= nums.length <= 1051 <= nums[i] <= 1041 <= x <= 109
Solutions
This one was fun.
Language: javascript()DONE
CPU Performance16.32%
x
Memory Performance59.38%
x
/**
* @param {number[]} nums
* @param {number} x
* @return {number}
*/
var minOperations = function(nums, x) {
const n = nums.length;
let total = 0;
for (const num of nums) {
total += num;
}
const target = total - x;
let left = 0;
let sum = 0;
let res = -1;
for (let right = 0; right < n; right++) {
sum += nums[right];
while (sum > target) {
sum -= nums[left];
left++;
}
if (sum === target) {
res = Math.max(res, right - left + 1);
}
}
return res === -1 ? -1 : n - res;
};