Sword finger offer II 012 The sum of left and right subarrays is equal

The finger of the sword Offer II 012. The sum of the left and right subarrays is equal

class Solution {
    
public:
    int pivotIndex(vector<int>& nums) {
    
		int total=accumulate(nums.begin(),nums.end(),0);
		int sum=0;
		for(int i=0;i<nums.size();++i){
    
			if(2*sum+nums[i]==total)
				return i;
			sum+=nums[i];
		}
		return -1;
    }
};