[LeetCode] 125. Same Tree (C#)

Young_A 2024. 1. 12. 09:44

LeetCode - Problems - Algorithms - 125. Same Tree

Same Tree - LeetCode

Can you solve this real interview question? Same Tree - 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

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My Solution (C#)

/**
 * Definition for a binary tree node.
 * public class TreeNode {
 *     public int val;
 *     public TreeNode left;
 *     public TreeNode right;
 *     public TreeNode(int val=0, TreeNode left=null, TreeNode right=null) {
 *         this.val = val;
 *         this.left = left;
 *         this.right = right;
 *     }
 * }
 */
public class Solution {
    public bool IsSameTree(TreeNode p, TreeNode q) {
        //time complexcity O(p+q)

        //comparing nulls and/or singles //only comparing nulls
        if (p == null && q == null) return true;
        if (p == null || q == null) return false;

        //first thing to check (root)
        if (p.val != q.val){ return false;}

        //comparing lower level //left and right both
        //recursively continue lower and lower
        //until node is not equal => false
        //or/and node is null =>true
        return IsSameTree(p.left, q.left) && IsSameTree(p.right, q.right);
    }
}