# Find the node whose xor with x gives minimum value

Given a tree, and the weights of all the nodes and an integer **x**, the task is to find a node **i** such that **weight[i] xor x** is minimum.

**Examples:**

Input:

x = 15

Output:3

Node 1: 5 xor 15 = 10

Node 2: 10 xor 15 = 5

Node 3: 11 xor 15 = 4

Node 4: 8 xor 15 = 7

Node 5: 6 xor 15 = 9

**Approach:** Perform dfs on the tree and keep track of the node whose weighted xor with **x** gives the minimum value.

Below is the implementation of above approach:

`// C++ implementation of the approach ` `#include <bits/stdc++.h> ` `using` `namespace` `std; ` ` ` `int` `minimum = INT_MAX, x, ans; ` ` ` `vector<` `int` `> graph[100]; ` `vector<` `int` `> weight(100); ` ` ` `// Function to perform dfs to find ` `// the minimum xored value ` `void` `dfs(` `int` `node, ` `int` `parent) ` `{ ` ` ` `// If current value is less than ` ` ` `// the current minimum ` ` ` `if` `(minimum > (weight[node] ^ x)) { ` ` ` `minimum = weight[node] ^ x; ` ` ` `ans = node; ` ` ` `} ` ` ` `for` `(` `int` `to : graph[node]) { ` ` ` `if` `(to == parent) ` ` ` `continue` `; ` ` ` `dfs(to, node); ` ` ` `} ` `} ` ` ` `// Driver code ` `int` `main() ` `{ ` ` ` `x = 15; ` ` ` ` ` `// Weights of the node ` ` ` `weight[1] = 5; ` ` ` `weight[2] = 10; ` ` ` `weight[3] = 11; ` ` ` `weight[4] = 8; ` ` ` `weight[5] = 6; ` ` ` ` ` `// Edges of the tree ` ` ` `graph[1].push_back(2); ` ` ` `graph[2].push_back(3); ` ` ` `graph[2].push_back(4); ` ` ` `graph[1].push_back(5); ` ` ` ` ` `dfs(1, 1); ` ` ` ` ` `cout << ans; ` ` ` ` ` `return` `0; ` `} ` |

*chevron_right*

*filter_none*

**Output:**

3

## Recommended Posts:

- Find the node whose sum with X has minimum set bits
- Find the node whose absolute difference with X gives minimum value
- Find the node with minimum value in a Binary Search Tree
- Find the node with minimum value in a Binary Search Tree using recursion
- Minimum edges to be added in a directed graph so that any node can be reachable from a given node
- Minimum and maximum node that lies in the path connecting two nodes in a Binary Tree
- Find next right node of a given key | Set 2
- Find next right node of a given key
- Find the node whose xor with x gives maximum value
- Find n-th node of inorder traversal
- Find the node whose sum with X has maximum set bits
- Find mirror of a given node in Binary tree
- Find the Kth node in the DFS traversal of a given subtree in a Tree
- Find the node whose absolute difference with X gives maximum value
- Find root of the tree where children id sum for every node is given

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.