Count_Binary_substrings

class Solution {
public:
    int countBinarySubstrings(string s) {
        int n = s.size();
        int i = 0, j = 0;
        int cnt = 0, ans = 0;
        while (i < n and j < n) {
            if (s[i] == s[j]) {
                cnt++;
                j++;
            }
            else {
                cnt--;
                j++;
            }

            if (cnt == 0) {
                ans++;
                i++;
                j = i;
            }
            if (j == n) {
                cnt = 0;
                i++;
                j = i;
            }
        }

        return ans;
    }
};