100 Same Tree

Given two binary trees, 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:     1         1
          / \       / \
         2   3     2   3

        [1,2,3],   [1,2,3]

Output: true

/**
 * 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 true;
        else if(p==null || q==null) return false;
        else if(p.val!=q.val)return false;
        
        else{
            return isSameTree(p.left,q.left) &&  isSameTree(p.right,q.right);
        }
    }
}

//Approach

      //p(tree)    q(tree)

Input:     1         1
          / \       / \
         2   3     2   3
    
    
    //Cases 1 p==null && q==null   true
    //Cases 2 p==null || q==null   false
    //Cases 3 p.val != q.val       false
    // -------------MOVE---------------- (R)