25. 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
    uint16_t res = 0;

    if (mode > 7) mode = 7;         // 3 bits max
    if (speed > 31) speed = 31;     // 5 bits max
    if (status > 63) status = 63;   // 6 bits max
    res |= (mode);
    res |= ((speed & 0x1F) << 3);
    // res |= ((speed & 0x1F) << 5);
    res |= ((status & 0x3F) << 10);

    return res;
}

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;
}