GitHub_collection_leetcode/algorithms/cpp/checkIfBinaryStringHasAtMostOneSegmentOfOnes/CheckIfBinaryStringHasAtMostOneSegmentOfOnes.cpp

// Source : https://leetcode.com/problems/check-if-binary-string-has-at-most-one-segment-of-ones/
// Author : Hao Chen
// Date   : 2021-03-07

/***************************************************************************************************** 
 *
 * Given a binary string s without leading zeros, return true if s contains at most one 
 * contiguous segment of ones. Otherwise, return false.
 * 
 * Example 1:
 * 
 * Input: s = "1001"
 * Output: false
 * Explanation: The ones do not form a contiguous segment.
 * 
 * Example 2:
 * 
 * Input: s = "110"
 * Output: true
 * 
 * Constraints:
 * 
 * 	1 <= s.length <= 100
 * 	s[i] is either '0' or '1'.
 * 	s[0] is '1'.
 ******************************************************************************************************/

class Solution {
public:
    bool checkOnesSegment(string s) {
        int i=0;
        while(i<s.size() && s[i]=='1') i++; 
        while(i<s.size() && s[i]=='0') i++;
        if(i<s.size() && s[i]=='1') return false;
        return true;
    }
};