Macro-Based Register Config Helper

Code

#include <stdio.h>
#include <stdint.h>
uint16_t reg;
// Define macros here
#define reg_enable(enable) reg|=enable;
#define reg_mode(mode) reg|=(mode<<1);
#define reg_speed(speed) reg|=(speed<<3);

uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    // Use macros to set fields
    reg_enable(enable);
    reg_mode(mode);
    reg_speed(speed);
    return reg;
}

int main() {
    uint8_t enable, mode, speed;
    scanf("%hhu %hhu %hhu", &enable, &mode, &speed);

    uint16_t reg = build_register(enable, mode, speed);
    printf("%u", reg);
    return 0;
}

Solving Approach