Same Tree

Same Tree

Given two binary trees, write a function to check if they are equal or not.

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

This problem is kind of easy compared to other binary tree problems on leetcode. We just need to make sure the value of every node and the shape of the binary tree is completely the same.

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