LeetCode-1221. Split a String in Balanced Strings

Balanced strings are those who have equal quantity of 'L' and 'R' characters.

Given a balanced string ​​s​​ split it in the maximum amount of balanced strings.

Return the maximum amount of splitted balanced strings.

 

Example 1:

Input: s = "RLRRLLRLRL"
Output: 4
Explanation: s can be split into "RL", "RRLL", "RL", "RL", each substring contains same number of 'L' and 'R'.

Example 2:

Input: s = "RLLLLRRRLR"
Output: 3
Explanation: s can be split into "RL", "LLLRRR", "LR", each substring contains same number of 'L' and 'R'.

Example 3:

Input: s = "LLLLRRRR"
Output: 1
Explanation: s can be split into "LLLLRRRR".

Example 4:

Input: s = "RLRRRLLRLL"
Output: 2
Explanation: s can be split into "RL", "RRRLLRLL", since each substring contains an equal number of 'L' and 'R'

 

Constraints:

• ​​1 <= s.length <= 1000​​
• ​​s[i] = 'L' or 'R'​​

​​题解：​​

​​题目没说清楚能不能恰好分割完，其实不用完全分割。​​

class Solution {
public:
    int balancedStringSplit(string s) {
        int res = 0;
        int r = 0, l = 0;
        for (int i = 0; i < s.length(); i++) {
            if (s[i] == 'R') {
                r++;
            }
            if (s[i] == 'L') {
                l++;
            }
            if (l == r) {
                res++;
                l = r = 0;
            }
        }
        return res;
    }
};