[프로그래머스] 쇠막대기

https://programmers.co.kr/learn/courses/30/lessons/42585

프로그래머스

function solution(arrangement) {
  var answer = 0;
  var stack = [];

  for (var i = 0; i < arrangement.length; i++) {
    if (arrangement[i] == "(") {
      stack.push(arrangement[i]);
      if (arrangement[i + 1] && arrangement[i + 1] == ")") {
        stack.pop();
        answer += stack.length;
        i++;
      }
    } else if (arrangement[i] == ")") {
      if (arrangement[i - 1] == ")") {
        answer++;
        stack.pop();
      }
    }
  }

  return answer;
}