Bitwise Operators in C HackerRank Solution

Problem Statement

In this challenge, you will use logical bitwise operators. All data is stored in its binary representation. The logical operators, and C language, use 1 to represent true and 0 to represent false. The logical operators compare bits in two numbers and return true or false, 1 or 0, for each bit compared.

Bitwise AND operator & The output of bitwise AND is 1 if the corresponding bits of two operands is 1. If either bit of an operand is 0, the result of corresponding bit is evaluated to 0. It is denoted by &.
Bitwise OR operator | The output of bitwise OR is 1 if at least one corresponding bit of two operands is 1. It is denoted by |.
Bitwise XOR (exclusive OR) operator ^ The result of bitwise XOR operator is 1 if the corresponding bits of two operands are opposite. It is denoted by ⊕ .

For example, for integers 3 and 5,

3 = 00000011 (In Binary)
5 = 00000101 (In Binary)

AND operation        OR operation        XOR operation
  00000011             00000011            00000011
& 00000101           | 00000101          ^ 00000101
  ________             ________            ________
  00000001  = 1        00000111  = 7       00000110  = 6

Example

N = 3

K = 3

The results of the comparisons are below:

a b   and or xor
1 2   0   3  3
1 3   1   3  2
2 3   2   3  1

For the and comparison, the maximum is 2. For the comparison, none of the values is less than k, so the maximum is 0. For the xor comparison, the maximum value less than k is 2. The function should print:

2
0
2

Function Description

Complete the calculate_the_maximum function in the editor below.

calculate_the_maximum has the following parameters:

• int n: the highest number to consider
• int k: the result of a comparison must be lower than this number to be considered

Task

Print the maximum values for the and, or and xor comparisons, each on a separate line.

Constraints:

• 2 <= n <= 10^3
• 2 <= k <= n

Input Format

• The only line contains 2 space-separated integers, n and k.

Example 1:

5 4

Output

2
3
3

Explanation

n = 4 , k = 5

S = { 1, 2, 3, 4, 5 }

All possible value of a and b are :

1. a = 1 , b = 2; a&b = 0; a | b = 3; a ⊕ b = 3;
2. a = 1 , b = 3; a&b = 1; a | b = 3; a ⊕ b = 2;
3. a = 1 , b = 4; a&b = 0; a | b = 5; a ⊕ b = 5;
4. a = 1 , b = 5; a&b = 1; a | b = 5; a ⊕ b = 4;
5. a = 2 , b = 3; a&b = 2; a | b = 3; a ⊕ b = 1;
6. a = 2 , b = 4; a&b = 0; a | b = 6; a ⊕ b = 6;
7. a = 2 , b = 5; a&b = 0; a | b = 7; a ⊕ b = 7;
8. a = 3 , b = 4; a&b = 0; a | b = 7; a ⊕ b = 7;
9. a = 3 , b = 5; a&b = 1; a | b = 7; a ⊕ b = 6;
10. a = 4 , b = 5; a&b = 4; a | b = 5; a ⊕ b = 1;

• The maximum possible value of a&b that is also < (k=4) is 2, so we print 2 on the first line.
• The maximum possible value of a | b that is also < (k=4) is 3, so we print 3 on the second line.
• The maximum possible value of  a ⊕ b that is also < (k=4) is 3, so we print 3 on  third line.

Bitwise Operators in C HackerRank Solution Code

#include <stdio.h>
#include <string.h>
#include <math.h>
#include <stdlib.h>

void calculate_the_maximum(int n, int k) {
 int max_and = 0, max_or = 0, max_xor = 0;
    for (int i = 1; i <= n; i++) {
        for (int j = i + 1; j <= n; j++) {
            int temp_and = i & j;
            int temp_or = i | j;
            int temp_xor = i ^ j;
            if (temp_and > max_and && temp_and < k) {
                max_and = temp_and;
            }
            if (temp_or > max_or && temp_or < k) {
                max_or = temp_or;
            }
            if (temp_xor > max_xor && temp_xor < k) {
                max_xor = temp_xor;
            }
        }
    }
    printf("%d\n%d\n%d", max_and, max_or, max_xor);
}

int main() {
    int n, k;
  
    scanf("%d %d", &n, &k);
    calculate_the_maximum(n, k);
 
    return 0;
}

Explanation of Approach

The above program finds the maximum values of bitwise AND, OR, and XOR operations for all pairs of integers from 1 to n, with the condition that the result must be less than a given integer k. Here’s a brief walkthrough of the main components of the code:

1. Function Declaration and Definition: The calculate_the_maximum function is defined to perform the core logic of the program. It takes two parameters, n and k, where n is the upper bound of the integer range (1 to n) and k is the threshold value that the results of the bitwise operations must not exceed.
2. Nested Loops for Pairwise Operations: Inside calculate_the_maximum, two nested for loops iterate over all unique pairs of integers in the range [1, n], where the inner loop starts from i + 1 to ensure that each pair is considered only once and that i is always less than j.
3. Bitwise Operations and Condition Checks: For each pair (i, j), the program computes the bitwise AND (i & j), OR (i | j), and XOR (i ^ j) operations. It then checks if the result of each operation is greater than the current maximum and less than k. If both conditions are met, the program updates the maximum value for that operation.
4. Output: After iterating through all pairs, the program prints the maximum values found for the bitwise AND, OR, and XOR operations, each on a new line, in that order.

Read Also

Dynamic Array in c Hackerrank Solution

Try out our free resume checker service where our Industry Experts will help you by providing resume score based on the key criteria that recruiters and hiring managers are looking for.