Pack Multiple Fields into a 16-bit Control Register

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

uint16_t pack_register(uint8_t mode, uint8_t speed, uint8_t status) {
    // Your logic here
    uint8_t reserved = 0;
    uint8_t pos[] = {3, 5, 2, 6};
    uint8_t val[] = {mode, speed, reserved, status};
    uint16_t clean_mask = 0xffff;
    uint16_t result;
    uint8_t cur_pos = 0;

    for(uint8_t i = 0; i < 4; i++)
    {
        result |= (val[i] << cur_pos) & ~(clean_mask << (cur_pos + pos[i]));
        cur_pos += pos[i];  
    }

    return result;    
}

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

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