分割平衡字符串

var balancedStringSplit = function(s) {
  let count = 0;
  let balance = 0;
  for(let i = 0; i < str.length; i++) {
    if (str[i] === 'L') balance++;
    else balance--;
    if (balance === 0) count++;
  }
  return count;
};
balancedStringSplit('LLRRLRRL');

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