100. Same Tree

https://leetcode.com/problems/same-tree/

C++

/**
 * Definition for a binary tree node.
 * struct TreeNode {
 *     int val;
 *     TreeNode *left;
 *     TreeNode *right;
 *     TreeNode() : val(0), left(nullptr), right(nullptr) {}
 *     TreeNode(int x) : val(x), left(nullptr), right(nullptr) {}
 *     TreeNode(int x, TreeNode *left, TreeNode *right) : val(x), left(left), right(right) {}
 * };
 */
class Solution {
public:
    bool isSameTree(TreeNode* p, TreeNode* q) {
        if (p == nullptr && q == nullptr) {
            return true;
        }
        if (p == nullptr || q == nullptr) {
            return false;
        }
        return p->val == q->val && isSameTree(p->left, q->left) && isSameTree(p->right, q->right);
    }
};

Go

/**
 * Definition for a binary tree node.
 * type TreeNode struct {
 *     Val int
 *     Left *TreeNode
 *     Right *TreeNode
 * }
 */
func isSameTree(p *TreeNode, q *TreeNode) bool {
    if p == nil && q == nil {
        return true
    }
    if p == nil || q == nil {
        return false
    }
    return p.Val == q.Val && isSameTree(p.Left, q.Left) && isSameTree(p.Right, q.Right)
}

JavaScript

/**
 * Definition for a binary tree node.
 * function TreeNode(val) {
 *     this.val = val;
 *     this.left = this.right = null;
 * }
 */
/**
 * @param {TreeNode} p
 * @param {TreeNode} q
 * @return {boolean}
 */
function isSameTree(p, q) {
  if (!p && !q) {
    return true
  }
  if (!p || !q) {
    return false
  }
  return p.val === q.val && isSameTree(p.left, q.left) && isSameTree(p.right, q.right)
}

Python

# Definition for a binary tree node.
# class TreeNode(object):
#     def __init__(self, x):
#         self.val = x
#         self.left = None
#         self.right = None


class Solution(object):

    def isSameTree(self, p, q):
        """
        :type p: TreeNode
        :type q: TreeNode
        :rtype: bool
        """
        if not p and not q:
            return True
        if not p or not q:
            return False
        return p.val == q.val and self.isSameTree(p.left, q.left) and self.isSameTree(p.right, q.right)