Bit Operations using Macros

Code

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

#define set_bits_2_and_7 (reg |= (1<<2)|(1<<7))
#define clear_bit_3 reg &= ~(1<<3)
#define toggle_bit_5 reg ^= (1<<5)


uint8_t modify_register(uint8_t reg) {
    set_bits_2_and_7;
    clear_bit_3;
    toggle_bit_5;
    return reg;
}

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

Solving Approach