PROBLEM #1486 (XOR Operation in an Array | Math, Bit Manipulation)

You are given an integer n and an integer start.

Define an array nums where nums[i] = start + 2 * i (0-indexed) and n == nums.length.

Return the bitwise XOR of all elements of nums.

Example 1

Input: n = 5, start = 0
Output: 8
Explanation: Array nums is equal to [0, 2, 4, 6, 8] where (0 ^ 2 ^ 4 ^ 6 ^ 8) = 8.

Where “^” corresponds to bitwise XOR operator.

Example 2

Input: n = 4, start = 3
Output: 8
Explanation: Array nums is equal to [3, 5, 7, 9] where (3 ^ 5 ^ 7 ^ 9) = 8.

Constraints

1 <= n <= 1000
0 <= start <= 1000
n == nums.length

SOLUTIONS

BIT MANIPULATION

JAVA

class Solution {
  public int xorOperation(int n, int start) {
      int res = start;
      for(int i = 1; i < n; i++)
          res ^= (start + 2 * i);
      return res;
  }
}