In this post, we are going to solve the 100. Same Tree problem of Leetcode. This problem 100. Same Tree is a Leetcode easy level problem. Let’s see the code, 100. Same Tree – Leetcode Solution.

Problem

Given the roots of two binary trees p and q, write a function to check if they are the same or not.

Two binary trees are considered the same if they are structurally identical, and the nodes have the same value.

Example 1 :

Input: p = [1,2,3], q = [1,2,3]
Output: true

Example 2 :

Input: p = [1,2], q = [1,null,2]
Output: false

Example 3 :

Input: p = [1,2,1], q = [1,1,2]
Output: false

Constraints

• The number of nodes in both trees is in the range [0, 100].
• -104 <= Node.val <= 104

Now, let’s see the code of 100. Same Tree – Leetcode Solution.

Same Tree – Leetcode Solution

100. Same Tree – Solution in Java

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

100. Same Tree – Solution in 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 == NULL || q == NULL) return (p == q);
        
        if(p->val != q->val) return false;
        
        return (isSameTree(p->left, q->left) && isSameTree(p->right, q->right));
    }
};

100. Same Tree – Solution in Python

# Definition for a binary tree node.
# class TreeNode(object):
#     def __init__(self, val=0, left=None, right=None):
#         self.val = val
#         self.left = left
#         self.right = right
class Solution(object):
    def isSameTree(self, p, q):
        if p and q:
            return p.val == q.val and self.isSameTree(p.left, q.left) and self.isSameTree(p.right, q.right)
        else:
            return p == q
        

Note: This problem 100. Same Tree is generated by Leetcode but the solution is provided by CodingBroz. This tutorial is only for Educational and Learning purpose.