Split a String in Balanced Strings

Balanced strings are those that have an 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 split 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".

 

Constraints:

  • 1 <= s.length <= 1000
  • s[i] is either 'L' or 'R'.
  • s is a balanced string.
SOLUTION:
class Solution:
    def balancedStringSplit(self, s: str) -> int:
        ctr = 0
        curr = 0
        for c in s:
            if curr == 0:
                ctr += 1
            if c == 'L':
                curr += 1
            else:
                curr -= 1
        if curr == 0:
            ctr += 1
        return ctr - 1

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