Hackerrank | 10 Days of Javascript | Day 6-Solution in JS | Bitwise-Operators-Hackerrank-Solution-in-JS

Hackerrank | 10 Days of Javascript | Day 6-Solution in JS | Bitwise-Operators-Hackerrank-Solution-in-JS

Objective

Today, we're practicing bitwise operations. Check the attached tutorial for more details.

Task

We define  to be a sequence of distinct sequential integers from  to ; in other words, . We want to know the maximum bitwise AND value of any two integers,  and  (where ), in sequence  that is also less than a given integer, .

Complete the function in the editor so that given  and , it returns the maximum .

Note: The  symbol represents the bitwise AND operator.

Input Format

The first line contains an integer, , denoting the number of function calls.
Each of the  subsequent lines defines a dataset for a function call in the form of two space-separated integers describing the respective values of  and .

Constraints

Output Format

Return the maximum possible value of  for any  in sequence .

Sample Input 0

3
5 2
8 5
2 2

Sample Output 0

1
4
0

Explanation 0

We perform the following  function calls:

1. When  and , we have the following possible  and  values in set :

   The maximum of any  that is also  is , so we return .

2. When  and , the maximum of any  in set  is  (see table above), so we return .
3. When  and , the maximum of any  in set  is  (see table above), so we return .

Sample Input 1

2
9 2
8 3

Sample Output 1

1
2

Explanation 1

We perform the following  function calls:

1. When  and , the maximum of any  in set  is  (see table above), so we return .
2. When  and , the maximum of any  in set  is  (see table above), so we return .
3. 
   

https://www.hackerrank.com/challenges/js10-bitwise/problem

Day 6: Bitwise Operators Solution in JS

'use strict';

process.stdin.resume();
process.stdin.setEncoding('utf-8');

let inputString = '';
let currentLine = 0;

process.stdin.on('data', inputStdin => {
    inputString += inputStdin;
});

process.stdin.on('end', _ => {
    inputString = inputString.trim().split('\n').map(string => {
        return string.trim();
    });
    
    main();    
});

function readLine() {
    return inputString[currentLine++];
}
function getMaxLessThanK(n, k) {
    let largest = 0;
    let current = 0;
    for (let i = 1; i < n; i++) {
        for (let x = i + 1; x <= n; x++) {
            current = i & x;
            if (current < k && current < n && current > largest) {
                largest = current;
            }
        }
    }
    return largest;
}

function main() {
    const q = +(readLine());
    
    for (let i = 0; i < q; i++) {
        const [n, k] = readLine().split(' ').map(Number);
        
        console.log(getMaxLessThanK(n, k));
    }
}