Macro-Based Register Config Helper

Code

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

// Define macros here
#define ENABLE(E, x)    E = (E | x)
#define MODE(E, x)      E = (E |(x << 1))
#define SPEED(E, x)     E = (E | (x << 3))
#define RESERVED(E)     E = (E & ~((1 << 6)))
uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    // Use macros to set fields
    uint16_t res = 0;
    ENABLE(res, enable);
    MODE(res, mode);
    SPEED(res, speed);
    RESERVED(res);
    return res;
}

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