1422. Maximum Score After Splitting a String

Given a string s of zeros and ones, return the maximum score after splitting the string into two non-empty substrings (i.e. left substring and right substring).

The score after splitting a string is the number of zeros in the left substring plus the number of ones in the right substring.

class Solution {
public:
    int maxScore(string s) {
        int z = 0, o = count(begin(s),end(s),'1');
        int res = 0;
        for(int i = 0; i < s.length() - 1; i++) {
            if(s[i] == '1') o -= 1;
            else z += 1;
            res = max(res, o + z);
        }
        return res;
    }
};