Maximize Binary String Score - Google Top Interview Questions

Problem Statement :

You are given a binary string s containing "1"s and "0"s. 
Consider splitting the string into two non-empty substrings such that a + b = s. 
The score of this split is defined to be the sum of the number of "0"s in a plus the number of "1"s in b. Return the maximum score possible.


2 ≤ n ≤ 100,000 where n is the length of s

Example 1


s = "001001110111"




We can split the string into "00100" + "1110111". Then, the score is 4 + 6 = 10`.

Solution :


                        Solution in C++ :

int solve(string s) {
    int left_zeroes = 0, right_ones = 0;
    for (auto &ch : s) {
        right_ones += ch == '1';
    int ans = 0;
    for (int i = 0; i < s.length() - 1; i++) {
        right_ones -= s[i] == '1';
        left_zeroes += s[i] == '0';
        ans = max(ans, left_zeroes + right_ones);
    return ans;

                        Solution in Java :

class Solution {
    public int solve(String s) {
        int c1 = 0;
        for (char c : s.toCharArray()) {
            if (c == '1')
        int max = 0, curr = c1;
        if (c1 == 0 || c1 == s.length())
            return s.length() - 1;
        for (int i = 0; i < s.length() - 1; i++) {
            char c = s.charAt(i);
            if (c == '0') {
            } else
            max = Math.max(max, curr);
        return max;

                        Solution in Python : 
class Solution:
    def solve(self, s):
        ones = s.count("1")
        zeros = 0
        ans = 0
        for i in range(len(s) - 1):
            if s[i] == "0":
                zeros += 1
                ones -= 1
            ans = max(ans, ones + zeros)
        return ans

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