100. Same Tree.java

//OPTIMISED SOLUTION
/**
 * 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;
            if(p==null || q==null) return false;
            if(p.val!=q.val) return false;
            return (isSameTree(p.left,q.left)) && (isSameTree(p.right,q.right));

    }
}