Macro-Based Register Config Helper

Code

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

// Define macros here
#define ENABLE(r, v) (r) |= (v & 0x01)
#define MODE(r, v) (r) |= ((v & 0x03) << 1)
#define SPEED(r, v) (r) |= ((v & 0x07) << 3)

uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    uint16_t control = 0;
    ENABLE(control, enable);
    MODE(control, mode);
    SPEED(control, speed);

    return control;
}

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