Determine if Brackets/Parenthesis are Nested Correctly

gistfile1.txt

const map = { '(': ')', '[': ']', '{': '}' };

function nestedBrackets(s) {
  const stack = [];

  for (let i = 0; i < s.length; i++) {
    if (s[i] === '{' || s[i] === '[' || s[i] === '(') {
      stack.push(s[i]);
    } else if (s[i] === '}' || s[i] === ']' || s[i] === ')') {
      if (map[stack[stack.length - 1]] !== s[i]) {
        return 0;
      }

      stack.pop();
    }
  }

  if (stack.length !== 0) {
    return 0;
  }

  return 1;
}