Find the single missing number in an array containing numbers from 1 to n using XOR.

Difficulty: Hard

Phase: 6 · Mixed Logical Challenges

XP Reward: 30 XP

Topics: Mixed Logical Challenges, Hard

Supported Languages: Python, JavaScript, C, C++, Java

Problem Description

Given array of N-1 integers from range 1 to N, find the single missing number using bitwise XOR. Input Format: Read input from standard input (stdin). Output Format: Print the result to standard output (stdout).

Constraints

-10^9 <= N <= 10^9

Examples

Example 1

Input: 4 1 2 4

Output: 3

Explanation: Sample execution for input 4 1 2 4