Count Substrings With All 1s - Google Top Interview Questions

                        Solution in C++ :

int solve(string s) {
    int i = 0, ans = 0, mod = 1e9 + 7;
    for (int j = 0; j < s.length(); j++) {
        if (s[j] == '0')
            i = j + 1;
        else
            ans = (ans + j - i + 1) % mod;
    }
    return ans;
}
                    

                        Solution in Java :

import java.util.*;

class Solution {
    public int solve(String s) {
        int tempResult = 0;
        int result = 0;
        for (int i = 0; i < s.length(); i++) {
            if (s.charAt(i) == '1') {
                tempResult++;
            } else {
                while (tempResult > 0) {
                    result += tempResult;
                    tempResult--;
                }
            }
        }
        while (tempResult > 0) {
            result += tempResult;
            tempResult--;
        }

        return result;
    }
}
                    

                        Solution in Python : 
                            
class Solution:
    def solve(self, s):
        a = 0
        count = 0
        for i in range(len(s)):
            if s[i] == "0":
                a = 0
            else:
                a += 1
                count += a
        return count