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XOR Operation in an Array - Easy - LeetCode - MiniTV

XOR Operation in an Array - Easy - LeetCode - मिनी टीवी

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.

 

Example 3:

Input: n = 1, start = 7

Output: 7

 

Example 4:

Input: n = 10, start = 5

Output: 2

 

Constraints:

1 <= n <= 1000

0 <= start <= 1000

n == nums.length

 

Solution:

using System;
using System.Collections.Generic;
using System.Text;

namespace LeetCode.AskGif.Easy.Array
{
    public class XorOperationSoln
    {
        public int XorOperation(int n, int start)
        {
            int num = 0;
            int xor = 0;
            for (int i = 0; i < n; i++)
            {
                num = start + 2 * i;
                xor = xor ^ num;
            }

            return xor;
        }
    }
}

 

Time Complexity: O(n)

Space Complexity: O(1)

 

Unit Tests:

using LeetCode.AskGif.Easy.Array;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using System;
using System.Collections.Generic;
using System.Text;

namespace CodingUnitTest.Easy.Array
{
    [TestClass]
    public class XorOperationSolnTests
    {
        [TestMethod]
        public void XorOperationSoln_First()
        {
            var n = 5;
            var start = 0;
            var expected = 8;
            
            var res = new XorOperationSoln().XorOperation(n, start);
            Assert.AreEqual(expected, res);
        }

        [TestMethod]
        public void XorOperationSoln_Second()
        {
            var n = 4;
            var start = 3;
            var expected = 8;

            var res = new XorOperationSoln().XorOperation(n, start);
            Assert.AreEqual(expected, res);
        }

        [TestMethod]
        public void XorOperationSoln_Third()
        {
            var n = 1;
            var start = 7;
            var expected = 7;

            var res = new XorOperationSoln().XorOperation(n, start);
            Assert.AreEqual(expected, res);
        }

        [TestMethod]
        public void XorOperationSoln_Fourth()
        {
            var n = 10;
            var start = 5;
            var expected = 2;

            var res = new XorOperationSoln().XorOperation(n, start);
            Assert.AreEqual(expected, res);
        }

    }
}