# Check for identical binary trees

Written by

studymite

## Problem

We need to check that the given trees are identical or not.

## Approach

We will check for each node in both the trees.

There will be three cases:

• If the root of both trees is NULL this means trees are identical.
• If one node is NULL and the other is not, this means trees are not identical.
• If both node’s data is not equal then trees are not identical.
• Now we will recursively traverse all the nodes and follow the above steps for every node.
``````#include<bits/stdc++.h>
using namespace std;
struct Node{
int data;
Node* left;
Node* right;
Node(int data){
this->data = data;
left = right = NULL;
}
};
bool isIdentical(Node *root1, Node *root2){
if(root1 == NULL && root2 == NULL) return true;
if((root1 &amp;&amp; !root2) || (!root1 &amp;&amp; root2)) return false;

if(root1-&gt;data != root2-&gt;data) return false;

return isIdentical(root1-&gt;left, root2-&gt;left) &amp;&amp; isIdentical(root1-&gt;right, root2-&gt;right);

}
int main() {
/*
1
/
2      3
/   \   /
4     5 6    7
/
struct Node root = new Node(1);
root->left = new Node(2);
root->left->left = new Node(4);
root->left->right = new Node(5);
root->right = new Node(3);
root->right->left = new Node(6);
root->right->right = new Node(7);
cout<<isIdentical(root, root);
return 0;

````}````

TC – O(N)