XOR of all Array elements that are perfect squares

Given an array arr[] containing N integers, the task is to find the XOR of all the elements of this array that are perfect squares.

Examples:

Input: arr[] = {3, 9, 16, 12, 13, 15} 
Output: 25
Explanation: Only 9, 16 are the perfect squares in the given array.
So the XOR of 9 and 16 is 25, XOR = 9 ^ 16 = 25

Input: arr[] = { 3, 9, 12, 13, 15 } 
Output: 9
Explanation: Only 9 is the perfect square so the answer will be 9.

Approach: To solve the problem follow the below idea:

In order to find the XOR of perfect square elements in the array, simply iterate through the array and find if an element is a perfect square or not, and then calculate the XOR using. 

Follow the below steps to compute the answer: 

• Declare a variable ( say xor_arr) to store the answer and initialize it to 0.
• Iterate from the start of the array:
  • For each element in the array, check if it is a perfect square or not.
    • A simple way to check is if the ceil and floor of the square root of an element are equal then the number is a perfect square.
  • Find the XOR of the perfect square element and store it in the result variable using the ‘^’ operator.
• Return the xor_arr variable that stores the XOR of all perfect square elements in the array.

Below is the implementation of the above approach.

// C++ program to find the XOR of all elements in the array
// which are perfect squares
#include <bits/stdc++.h>
using namespace std;

// Function to find whether an element is perfect square
// or not
bool checkperfectsquare(int x)
{
    // If ceil and floor are equal the number is a
    // perfect square
    return ceil(sqrt(x)) == floor(sqrt(x));
}

int xorOfArray(int arr[], int n)
{
    // Stores final result
    int xor_arr = 0;

    // Iterating through every element in the array
    for (int i = 0; i < n; i++) {

        // Find XOR with the result
        if (checkperfectsquare(arr[i])) {
            xor_arr = xor_arr ^ arr[i];
        }
    }

    // Return the XOR
    return xor_arr;
}

// Driver Code
int main()
{
    int arr[] = { 3, 9, 16, 12, 13, 15 };
    int N = 6;

    // Function call
    cout << xorOfArray(arr, N);
    return 0;
}

// This code is contributed by Rohit Pradhan

// Java program to find the XOR of all elements in the array
// which are perfect squares
import java.io.*;
class GFG {

  // Function to find whether an element is perfect square
  // or not
  static boolean checkperfectsquare(int x)
  {

    // If ceil and floor are equal the number is a
    // perfect square
    return Math.ceil(Math.sqrt(x))
      == Math.floor(Math.sqrt(x));
  }

  static int xorOfArray(int[] arr, int n)
  {
    // Stores final result
    int xor_arr = 0;

    // Iterating through every element in the array
    for (int i = 0; i < n; i++) 
    {

      // Find XOR with the result
      if (checkperfectsquare(arr[i])) {
        xor_arr = xor_arr ^ arr[i];
      }
    }

    // Return the XOR
    return xor_arr;
  }

  public static void main(String[] args)
  {
    int[] arr = { 3, 9, 16, 12, 13, 15 };
    int N = arr.length;

    // Function call
    System.out.print(xorOfArray(arr, N));
  }
}

// This code is contributed by lokeshmvs21.

# Python3 program to find the XOR of
# all elements in the array
# which are perfect squares

import math

# Function to find whether
# an element is perfect square or not
def checkperfectsquare(x):
    
    # If ceil and floor are equal
    # the number is a perfect
    # square
    return math.ceil(math.sqrt(x)) == math.floor(math.sqrt(x))

def xorOfArray(arr, n):
    
    # Stores final result
    xor_arr = 0
    
    # Iterating through every element in
    # the array
    for i in range(n):
        
        # Find XOR with the result
        if checkperfectsquare(arr[i]):
            xor_arr = xor_arr ^ arr[i]
    
    # Return the XOR
    return xor_arr

# Driver Code
if __name__ == '__main__':
    arr = [3, 9, 16, 12, 13, 15]
    N = len(arr)
    
    # Function call
    print(xorOfArray(arr, N))

// C# program to find the XOR of all elements in the array
// which are perfect squares
using System;
class GFG {

  // Function to find whether an element is perfect square
  // or not
  static Boolean checkperfectsquare(int x)
  {

    // If ceil and floor are equal the number is a
    // perfect square
    return Math.Ceiling(Math.Sqrt(x))
      == Math.Floor(Math.Sqrt(x));
  }

  static int xorOfArray(int[] arr, int n)
  {
    // Stores final result
    int xor_arr = 0;

    // Iterating through every element in the array
    for (int i = 0; i < n; i++) 
    {

      // Find XOR with the result
      if (checkperfectsquare(arr[i])) {
        xor_arr = xor_arr ^ arr[i];
      }
    }

    // Return the XOR
    return xor_arr;
  }

  public static void Main()
  {
    int[] arr = { 3, 9, 16, 12, 13, 15 };
    int N = arr.Length;

    // Function call
    Console.Write(xorOfArray(arr, N));
  }
}

// This code is contributed by Saurabh Jaiswal

        // JavaScript code for the above approach

        // Function to find whether
        // an element is perfect square or not
        function checkperfectsquare(x) {

            // If ceil and floor are equal
            // the number is a perfect
            // square
            return Math.ceil(Math.sqrt(x)) == Math.floor(Math.sqrt(x))
        }
        function xorOfArray(arr, n) {

            // Stores final result
            let xor_arr = 0

            // Iterating through every element in
            // the array
            for (let i = 0; i < n; i++) {

                // Find XOR with the result
                if (checkperfectsquare(arr[i])) {
                    xor_arr = xor_arr ^ arr[i]
                }
            }
            // Return the XOR
            return xor_arr
        }
        
        // Driver Code
        arr = [3, 9, 16, 12, 13, 15]
        N = arr.length

        // Function call
        console.log(xorOfArray(arr, N))

 // This code is contributed by Potta Lokesh

25

Time Complexity: O(Nlog(N))
Auxiliary Space: O(1)