1221_Split_a_String_in_Balanced_Strings.cpp

/*
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'

来源：力扣（LeetCode）
链接：https://leetcode-cn.com/problems/split-a-string-in-balanced-strings
著作权归领扣网络所有。商业转载请联系官方授权，非商业转载请注明出处。
*/

#include <string>
using namespace std;

class Solution {
public:
    int balancedStringSplit(string s) {
		int res = 0;
		int pos = 0;
		for (size_t i = 0; i < s.size(); ++i) {
			if(s[i]=='L'){
				--pos;
			}
			else{
				++pos;
			}
			if(pos==0) ++res;
		}
		return res;
    }
};