Bit Operations using Macros

Code

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

uint8_t reg = 0b00000000 ; 
uint8_t modify_register(uint8_t reg) {
    reg |= (1<<2) | (1<<7) ; 
    reg &= ~(1<<3) ; 
    reg ^= (1<<5) ; 
    return reg;
}

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

Solving Approach