C bitwise integer absolute value

To obtain the absolute value of an integer using bitwise operators in C, you can follow the steps below:

  1. Declare a variable to store the original value of the integer.
  2. Use a bitwise operator, specifically the right shift operator (>>), to shift the integer to the right by the number of bits minus one.
  3. Use a bitwise XOR operator (^) to perform an exclusive OR operation between the shifted integer and the original integer.
  4. Use a bitwise subtraction operator (-) to subtract the result obtained from step 3 from the original integer.

Here is an example code snippet that demonstrates how to obtain the absolute value of an integer using bitwise operators in C:

#include <stdio.h>

int abs(int num) {
    int mask = num >> (sizeof(int) * 8 - 1);
    return (num + mask) ^ mask;
}

int main() {
    int num = -10;
    int absolute = abs(num);

    printf("The absolute value of %d is %d\n", num, absolute);

    return 0;
}

This code snippet defines a function abs() that takes an integer as input and returns its absolute value. The function uses the bitwise operations described above to achieve this. In the main() function, we test the abs() function by passing a negative number and printing the result.

When you run this code, it will output:

The absolute value of -10 is 10

I hope this code snippet helps you understand how to obtain the absolute value of an integer using bitwise operators in C. Let me know if you have any further questions.