Macro-Based Register Config Helper

Code

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

// Define macros here
#define ENABLE(reg,enable) ((reg)|(enable))
#define MODE(reg,mode) ((reg)|((mode)<<(1)))
#define SPEED(reg,speed) ((reg)|((speed)<<(3)))

uint16_t build_register(uint8_t enable, uint8_t mode, uint8_t speed) {
    // Use macros to set fields
    uint16_t reg_val = 0;
    reg_val = ENABLE(reg_val,enable);
    reg_val = MODE(reg_val,mode);
    reg_val = SPEED(reg_val,speed);
    return reg_val;
}

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