Description
Given an array of integers nums, calculate the pivot index where the sum of numbers to the left equals the sum of numbers to the right. Return -1 if no such index exists.
Examples
Input:
nums = [1,7,3,6,5,6]Output:
3Explanation:
Sum left of index 3 is 1+7+3=11, right is 5+6=11.
Input:
nums = [2,1,-1]Output:
0Explanation:
At index 0, left sum is 0 and right sum is 1+(-1)=0. Both sides are equal.
Input:
nums = [4,-2,3,1,-1,2]Output:
2Explanation:
Sum left of index 2 is 4+(-2)=2, right is 1+(-1)+2=2. This example demonstrates handling negative numbers in the array.
Constraints
- •
1 ≤ nums.length ≤ 10⁴