Day 29: Bitwise AND - HackerRank 30 days of code solution

Objective
Welcome to the last day! Today, we're discussing bitwise operations.

Task
Given set . Find two integers,  and  (where ), from set  such that the value of  is the maximum possible and also less than a given integer, . In this case,  represents the bitwise AND operator.

Input Format

The first line contains an integer, , the number of test cases.
Each of the  subsequent lines defines a test case as  space-separated integers,  and , respectively.

Constraints

Output Format

For each test case, print the maximum possible value of  on a new line.

Sample Input

3
5 2
8 5
2 2

Sample Output

1
4
0

Explanation

All possible values of  and  are:

The maximum possible value of  that is also  is , so we print  on a new line.

Solution :

import java.io.*;

import java.util.*;

public class Solution {

    public static void main(String[] args) {

        /* Enter your code here. Read input from STDIN. Print output to STDOUT. Your class should be named Solution. */

         Scanner sc = new Scanner(System.in);

        int T = sc.nextInt();

        for (int tc = 0; tc < T; tc++) {

            int N = sc.nextInt();

            int K = sc.nextInt();

            System.out.println(solve(N, K));

        }

        sc.close();

    }

    static int solve(int N, int K) {

        int result = 0;

        for (int A = 1; A <= N; A++) {

            for (int B = A + 1; B <= N; B++) {

                int current = A & B;

                if (current > result && current < K) {

                    result = current;

                }

            }

        }

        return result;

    }

}