same tree leetcode #100

sameTreeIterative. js

// Iterative solution: time complexity: O(n) | space complexity: O(n)
var isSameTree = function (p, q) {
  const q1 = [];
  q1.push(p);
  const q2 = [];
  q2.push(q);

  while (q1.length && q2.length) {
    const curr1 = q1.shift();
    const curr2 = q2.shift();
    // check for null
    if (curr1 === null || curr2 === null) {
      if (curr1 !== curr2) {
        return false;
      } else {
        continue;
      }
    }
    //check value
    if (curr1.val !== curr2.val) return false;

    // add children to queues
    q1.push(curr1.left, curr1.right);
    q2.push(curr2.left, curr2.right);
  }
  if (q1.length || q2.length) {
    return false;
  }
  return true;
};