Bit Operations using Macros

Code

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

#define SET(x)      (((x) |= ((1<<2) | (1<<7))))
#define CLEAR(x)    (((x) &= ~(1<<3)))
#define TOOGLE(x)   (((x) ^= (1<<5))) 

uint8_t modify_register(uint8_t reg) {
    uint8_t reg_val = 0;
    reg_val = SET(reg);
    reg_val = CLEAR(reg);
    reg_val = TOOGLE(reg); 
    return reg_val;
}

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

Solving Approach