Given two arrays A[] and B[] consisting of N positive integers, the task is to the Bitwise XOR of same indexed array elements after rearranging the array B[] such that the Bitwise XOR of the same indexed elements of the arrays A[] becomes equal.
Examples:
Input: A[] = {1, 2, 3}, B[] = {4, 6, 7}
Output: 5
Explanation:
Below are the possible arrangements:
- Rearrange the array B[] to {4, 7, 6}. Now, the Bitwise XOR of the same indexed elements are equal, i.e. 1 ^ 4 = 5, 2 ^ 7 = 5, 3 ^ 6 = 5.
After the rearrangements, required Bitwise XOR is 5.
Input: A[] = { 7, 8, 14 }, B[] = { 5, 12, 3 }
Output: 11
Explanation:
Below are the possible arrangements:
- Rearrange the array B[] to {12, 3, 5}. Now, the Bitwise XOR of the same indexed elements are equal, i.e. 7 ^ 12 = 11, 8 ^ 3 = 11, 14 ^ 5 = 11.
After the rearrangements, required Bitwise XOR is 11.
Naive Approach: The given problem can be solved based on the observation that the count of rearrangements can be at most N because any element in A[] can only be paired with N other integers in B[]. So, there are N candidate values for X. Now, simply XOR all the candidates with each element in A[] and check if B[] can be arranged in that order.
Below is the implementation of the above approach:
C++
// C++ program for the above approach #include <bits/stdc++.h> using namespace std; // Function to find all possible values // of Bitwise XOR such after rearranging // the array elements the Bitwise XOR // value at corresponding indexes is same void findPossibleValues( int A[], int B[], int n) { // Sort the array B sort(B, B + n); int C[n]; // Stores all the possible values // of the Bitwise XOR set< int > numbers; // Iterate over the range for ( int i = 0; i < n; i++) { // Possible value of K int candidate = A[0] ^ B[i]; // Array B for the considered // value of K for ( int j = 0; j < n; j++) { C[j] = A[j] ^ candidate; } sort(C, C + n); bool flag = false ; // Verify if the considered value // satisfies the condition or not for ( int j = 0; j < n; j++) if (C[j] != B[j]) flag = true ; // Insert the possible Bitwise // XOR value if (!flag) numbers.insert(candidate); } // Print all the values obtained for ( auto x : numbers) { cout << x << " " ; } } // Driver Code int main() { int A[] = { 7, 8, 14 }; int B[] = { 5, 12, 3 }; int N = sizeof (A) / sizeof (A[0]); findPossibleValues(A, B, N); return 0; } |
Java
// Java program for the above approach import java.util.*; class GFG { // Function to find all possible values // of Bitwise XOR such after rearranging // the array elements the Bitwise XOR // value at corresponding indexes is same static void findPossibleValues( int A[], int B[], int n) { // Sort the array B Arrays.sort(B); int []C = new int [n]; // Stores all the possible values // of the Bitwise XOR HashSet<Integer> numbers = new HashSet<Integer>(); // Iterate over the range for ( int i = 0 ; i < n; i++) { // Possible value of K int candidate = A[ 0 ] ^ B[i]; // Array B for the considered // value of K for ( int j = 0 ; j < n; j++) { C[j] = A[j] ^ candidate; } Arrays.sort(C); boolean flag = false ; // Verify if the considered value // satisfies the condition or not for ( int j = 0 ; j < n; j++) if (C[j] != B[j]) flag = true ; // Insert the possible Bitwise // XOR value if (!flag) numbers.add(candidate); } // Print all the values obtained for ( int x : numbers) { System.out.print(x+ " " ); } } // Driver Code public static void main(String[] args) { int A[] = { 7 , 8 , 14 }; int B[] = { 5 , 12 , 3 }; int N = A.length; findPossibleValues(A, B, N); } } // This code is contributed by 29AjayKumar |
Python3
# Python program for the above approach # Function to find all possible values # of Bitwise XOR such after rearranging # the array elements the Bitwise XOR # value at corresponding indexes is same def findPossibleValues(A, B, n): # Sort the array B B.sort(); C = [ 0 ] * n; # Stores all the possible values # of the Bitwise XOR numbers = set (); # Iterate over the range for i in range (n): # Possible value of K candidate = A[ 0 ] ^ B[i]; # Array B for the considered # value of K for j in range (n): C[j] = A[j] ^ candidate; C.sort(); flag = False ; # Verify if the considered value # satisfies the condition or not for j in range (n): if (C[j] ! = B[j]): flag = True ; # Insert the possible Bitwise # XOR value if ( not flag): numbers.add(candidate); # Print all the values obtained for x in numbers: print (x, end = " " ); # Driver Code A = [ 7 , 8 , 14 ]; B = [ 5 , 12 , 3 ]; N = len (A); findPossibleValues(A, B, N); # This code is contributed by gfgking. |
C#
// C# program for the above approach using System; using System.Collections.Generic; public class GFG { // Function to find all possible values // of Bitwise XOR such after rearranging // the array elements the Bitwise XOR // value at corresponding indexes is same static void findPossibleValues( int []A, int []B, int n) { // Sort the array B Array.Sort(B); int []C = new int [n]; // Stores all the possible values // of the Bitwise XOR HashSet< int > numbers = new HashSet< int >(); // Iterate over the range for ( int i = 0; i < n; i++) { // Possible value of K int candidate = A[0] ^ B[i]; // Array B for the considered // value of K for ( int j = 0; j < n; j++) { C[j] = A[j] ^ candidate; } Array.Sort(C); bool flag = false ; // Verify if the considered value // satisfies the condition or not for ( int j = 0; j < n; j++) if (C[j] != B[j]) flag = true ; // Insert the possible Bitwise // XOR value if (!flag) numbers.Add(candidate); } // Print all the values obtained foreach ( int x in numbers) { Console.Write(x+ " " ); } } // Driver Code public static void Main(String[] args) { int []A = { 7, 8, 14 }; int []B = { 5, 12, 3 }; int N = A.Length; findPossibleValues(A, B, N); } } // This code is contributed by 29AjayKumar |
Javascript
<script> // Javascript program for the above approach // Function to find all possible values // of Bitwise XOR such after rearranging // the array elements the Bitwise XOR // value at corresponding indexes is same function findPossibleValues(A, B, n) { // Sort the array B B.sort((a, b) => a - b); let C = new Array(n); // Stores all the possible values // of the Bitwise XOR let numbers = new Set(); // Iterate over the range for (let i = 0; i < n; i++) { // Possible value of K let candidate = A[0] ^ B[i]; // Array B for the considered // value of K for (let j = 0; j < n; j++) { C[j] = A[j] ^ candidate; } C.sort((a, b) => a - b); let flag = false ; // Verify if the considered value // satisfies the condition or not for (let j = 0; j < n; j++) if (C[j] != B[j]) flag = true ; // Insert the possible Bitwise // XOR value if (!flag) numbers.add(candidate); } // Print all the values obtained for (let x of numbers) { document.write(x + " " ); } } // Driver Code let A = [7, 8, 14]; let B = [5, 12, 3]; let N = A.length; findPossibleValues(A, B, N); // This code is contributed by gfgking. </script> |
11
Time Complexity: O(N2*log(N))
Auxiliary Space: O(N)
Efficient Approach: The above approach can also be optimized by not sorting the array and store the bit-wise-XOR of all elements of B[], and then the Bitwise XOR with all elements in C[]. Now if the result is 0 then it means both arrays have same elements. Follow the steps below to solve the problem:
- Initialize the variable, say x that stores the XOR of all the elements of the array B[].
- Initialize a set, say numbers[] to store only unique numbers..
- Iterate over the range [0, N) using the variable i and perform the following steps:
- Initialize the variables candidate as the XOR of A[0] and B[i] and curr_xor as x to see if it is 0 after performing the requires operations.
- Iterate over the range [0, N) using the variable j and perform the following steps:
- Initialize the variable y as the XOR of A[j] and candidate and XOR y with curr_xor.
- If curr_xor is equal to 0, then insert the value candidate into the set numbers[].
- After performing the above steps, print the set numbers[] as the answer.
Below is the implementation of the above approach.
C++
// C++ program for the above approach #include <bits/stdc++.h> using namespace std; // Function to find all possible values // of Bitwise XOR such after rearranging // the array elements the Bitwise XOR // value at corresponding indexes is same void findPossibleValues( int A[], int B[], int n) { // Stores the XOR of the array B[] int x = 0; for ( int i = 0; i < n; i++) { x = x ^ B[i]; } // Stores all possible value of // Bitwise XOR set< int > numbers; // Iterate over the range for ( int i = 0; i < n; i++) { // Possible value of K int candidate = A[0] ^ B[i]; int curr_xor = x; // Array B for the considered // value of K for ( int j = 0; j < n; j++) { int y = A[j] ^ candidate; curr_xor = curr_xor ^ y; } // This means all the elements // are equal if (curr_xor == 0) numbers.insert(candidate); } // Print all the possible value for ( auto x : numbers) { cout << x << " " ; } } // Driver Code int main() { int A[] = { 7, 8, 14 }; int B[] = { 5, 12, 3 }; int N = sizeof (A) / sizeof (A[0]); findPossibleValues(A, B, N); return 0; } |
Java
// Java code for above approach import java.util.*; class GFG{ // Function to find all possible values // of Bitwise XOR such after rearranging // the array elements the Bitwise XOR // value at corresponding indexes is same static void findPossibleValues( int A[], int B[], int n) { // Stores the XOR of the array B[] int x = 0 ; for ( int i = 0 ; i < n; i++) { x = x ^ B[i]; } // Stores all possible value of // Bitwise XOR HashSet<Integer> numbers = new HashSet<Integer>(); // Iterate over the range for ( int i = 0 ; i < n; i++) { // Possible value of K int candidate = A[ 0 ] ^ B[i]; int curr_xor = x; // Array B for the considered // value of K for ( int j = 0 ; j < n; j++) { int y = A[j] ^ candidate; curr_xor = curr_xor ^ y; } // This means all the elements // are equal if (curr_xor == 0 ) numbers.add(candidate); } // Print all the possible value for ( int i : numbers) { System.out.print(i + " " ); } } // Driver Code public static void main(String[] args) { int A[] = { 7 , 8 , 14 }; int B[] = { 5 , 12 , 3 }; int N = A.length; findPossibleValues(A, B, N); } } // This code is contributed by avijitmondal1998. |
Python3
# Python 3 program for the above approach # Function to find all possible values # of Bitwise XOR such after rearranging # the array elements the Bitwise XOR # value at corresponding indexes is same def findPossibleValues(A, B, n): # Stores the XOR of the array B[] x = 0 for i in range (n): x = x ^ B[i] # Stores all possible value of # Bitwise XOR numbers = set () # Iterate over the range for i in range (n): # Possible value of K candidate = A[ 0 ] ^ B[i] curr_xor = x # Array B for the considered # value of K for j in range (n): y = A[j] ^ candidate curr_xor = curr_xor ^ y # This means all the elements # are equal if (curr_xor = = 0 ): numbers.add(candidate) # Print all the possible value for x in numbers: print (x, end = " " ) # Driver Code if __name__ = = '__main__' : A = [ 7 , 8 , 14 ] B = [ 5 , 12 , 3 ] N = len (A) findPossibleValues(A, B, N) # This code is contributed by ipg2016107. |
C#
// C# code for above approach using System; using System.Collections.Generic; public class GFG { // Function to find all possible values // of Bitwise XOR such after rearranging // the array elements the Bitwise XOR // value at corresponding indexes is same static void findPossibleValues( int []A, int []B, int n) { // Stores the XOR of the array []B int x = 0; for ( int i = 0; i < n; i++) { x = x ^ B[i]; } // Stores all possible value of // Bitwise XOR HashSet< int > numbers = new HashSet< int >(); // Iterate over the range for ( int i = 0; i < n; i++) { // Possible value of K int candidate = A[0] ^ B[i]; int curr_xor = x; // Array B for the considered // value of K for ( int j = 0; j < n; j++) { int y = A[j] ^ candidate; curr_xor = curr_xor ^ y; } // This means all the elements // are equal if (curr_xor == 0) numbers.Add(candidate); } // Print all the possible value foreach ( int i in numbers) { Console.Write(i + " " ); } } // Driver Code public static void Main(String[] args) { int []A = { 7, 8, 14 }; int []B = { 5, 12, 3 }; int N = A.Length; findPossibleValues(A, B, N); } } // This code is contributed by shikhasingrajput |
Javascript
<script> // javascript code for above approach // Function to find all possible values // of Bitwise XOR such after rearranging // the array elements the Bitwise XOR // value at corresponding indexes is same function findPossibleValues(A, B, n) { // Stores the XOR of the array B var x = 0; for ( var i = 0; i < n; i++) { x = x ^ B[i]; } // Stores all possible value of // Bitwise XOR var numbers = new Set(); // Iterate over the range for ( var i = 0; i < n; i++) { // Possible value of K var candidate = A[0] ^ B[i]; var curr_xor = x; // Array B for the considered // value of K for ( var j = 0; j < n; j++) { var y = A[j] ^ candidate; curr_xor = curr_xor ^ y; } // This means all the elements // are equal if (curr_xor == 0) numbers.add(candidate); } // Print all the possible value for ( var i of numbers) { document.write(i + " " ); } } // Driver Code var A = [ 7, 8, 14 ]; var B = [ 5, 12, 3 ]; var N = A.length; findPossibleValues(A, B, N); // This code is contributed by shikhasingrajput </script> |
11
Time Complexity: O(N2)
Auxiliary Space: O(N) as using set “numbers”
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