Given two arrays A[] and B[] of N elements each. The task is to find the number of index pairs (i, j) such that i ? j and F(A[i] | A[j]) = B[j] where F(X) is the count of set bits in the binary representation of X.
Examples
Input: A[] = {5, 3, 2, 4, 6, 1}, B[] = {2, 2, 1, 4, 2, 3}
Output: 7
All possible pairs are (5, 5), (3, 3), (2, 2),
(2, 6), (4, 6), (6, 6) and (6, 1).
Input: A[] = {4, 3, 5, 6, 7}, B[] = {1, 3, 2, 4, 5}
Output: 4
Approach: Iterate through all the possible pairs (i, j) and check the count of set bits in their OR value. If the count is equal to B[j] then increment the count.
Below is the implementation of the above approach:
C++
// C++ implementation of the approach #include <bits/stdc++.h> using namespace std; // Function to return the count of pairs // which satisfy the given condition int solve( int A[], int B[], int n) { int cnt = 0; for ( int i = 0; i < n; i++) for ( int j = i; j < n; j++) // Check if the count of set bits // in the OR value is B[j] if (__builtin_popcount(A[i] | A[j]) == B[j]) { cnt++; } return cnt; } // Driver code int main() { int A[] = { 5, 3, 2, 4, 6, 1 }; int B[] = { 2, 2, 1, 4, 2, 3 }; int size = sizeof (A) / sizeof (A[0]); cout << solve(A, B, size); return 0; } |
Java
// Java implementation of the approach class GFG { // Function to return the count of pairs // which satisfy the given condition static int solve( int A[], int B[], int n) { int cnt = 0 ; for ( int i = 0 ; i < n; i++) for ( int j = i; j < n; j++) // Check if the count of set bits // in the OR value is B[j] if (Integer.bitCount(A[i] | A[j]) == B[j]) { cnt++; } return cnt; } // Driver code public static void main(String args[]) { int A[] = { 5 , 3 , 2 , 4 , 6 , 1 }; int B[] = { 2 , 2 , 1 , 4 , 2 , 3 }; int size = A.length; System.out.println(solve(A, B, size)); } } // This code is contributed by 29AjayKumar |
Python3
# Python3 implementation of the approach # Function to return the count of pairs # which satisfy the given condition def solve(A, B, n) : cnt = 0 ; for i in range (n) : for j in range (i, n) : # Check if the count of set bits # in the OR value is B[j] if ( bin (A[i] | A[j]).count( '1' ) = = B[j]) : cnt + = 1 ; return cnt # Driver code if __name__ = = "__main__" : A = [ 5 , 3 , 2 , 4 , 6 , 1 ]; B = [ 2 , 2 , 1 , 4 , 2 , 3 ]; size = len (A); print (solve(A, B, size)); # This code is contributed by AnkitRai01 |
C#
// C# implementation of the approach using System; class GFG { // Function to return the count of pairs // which satisfy the given condition static int solve( int []A, int []B, int n) { int cnt = 0; for ( int i = 0; i < n; i++) for ( int j = i; j < n; j++) // Check if the count of set bits // in the OR value is B[j] if (bitCount(A[i] | A[j]) == B[j]) { cnt++; } return cnt; } static int bitCount( long x) { // To store the count // of set bits int setBits = 0; while (x != 0) { x = x & (x - 1); setBits++; } return setBits; } // Driver code public static void Main(String []args) { int []A = { 5, 3, 2, 4, 6, 1 }; int []B = { 2, 2, 1, 4, 2, 3 }; int size = A.Length; Console.WriteLine(solve(A, B, size)); } } /* This code is contributed by PrinciRaj1992 */ |
Javascript
<script> // JavaScript implementation of the approach // Function to return the count of pairs // which satisfy the given condition function solve(A,B,n) { let cnt = 0; for (let i = 0; i < n; i++) for (let j = i; j < n; j++) // Check if the count of set bits // in the OR value is B[j] if (bitCount(A[i] | A[j]) == B[j]) { cnt++; } return cnt; } function bitCount(x) { // To store the count // of set bits let setBits = 0; while (x != 0) { x = x & (x - 1); setBits++; } return setBits; } // Driver code let A=[5, 3, 2, 4, 6, 1 ]; let B=[2, 2, 1, 4, 2, 3 ]; let size = A.length; document.write(solve(A, B, size)); // This code is contributed by rag2127 </script> |
7
Time Complexity: O(N2)
Auxiliary Space: O(1)
Ready to dive in? Explore our Free Demo Content and join our DSA course, trusted by over 100,000 neveropen!