1221-split-a-string-in-balanced-strings.py

"""
Problem Link: https://leetcode.com/problems/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'
"""
class Solution:
    def balancedStringSplit(self, s: str) -> int:
        count = res = 0
        for c in s:
          count += 1 if c == 'L' else -1
          res += count == 0
        return res