Bit Operations using Macros

Code

#include <stdio.h>
#include <stdint.h>

// Define bitwise macros here
#define SET_2_7_BITS(reg)   (reg | 0x84)
#define CLEAR_BIT_3(reg)    (reg & ~0x08)
#define TOGGLE_BIT_5(reg)   (reg ^ 0x20)

uint8_t modify_register(uint8_t reg) {
    // Apply operations in order
    reg = SET_2_7_BITS(reg);
    reg = CLEAR_BIT_3(reg);
    reg = TOGGLE_BIT_5(reg);

    return reg;
}

int main() {
    uint8_t reg;
    scanf("%hhu", &reg);
    printf("%u", modify_register(reg));
    return 0;
}

Solving Approach

Req:
- Create Macros for 
    - setting bit 2 & 7
    - clear bit 3
    - toggle bit 5
- use these macros in the function
- return the result

Input: 0
Output: 164 

(0000_0000 → 1010_0100)


Plan:
- create masks for each of the condition as macros for maintainability
- apply the mask to the input
- return the input