Valid Parentheses

Given a string s containing just the characters '(', ')', '{', '}', '[' and ']', determine if the input string is valid.

An input string is valid if:

1. Open brackets must be closed by the same type of brackets.
2. Open brackets must be closed in the correct order.
3. Every close bracket has a corresponding open bracket of the same type.

Input: s = "()"
Output: true

Input: s = "(]"
Output: false

const peak = (st) => st[st.length - 1];

const isValid = function (s) {
  if (!s || s.length === 1) return false;

  const st = [];
  const openBrackets = ["{", "(", "["];
  const map = {
    ")": "(",
    "}": "{",
    "]": "[",
  };

  let i = 0;
  while (i < s.length) {
    const curChar = s[i++];
    if (openBrackets.includes(curChar)) {
      st.push(curChar);
      continue;
    }

    if (peak(st) !== map[curChar]) {
      return false;
    }

    st.pop();
  }

  if (st.length) {
    return false;
  }

  return true;
};