25. Pack Multiple Fields into a 16-bit Control Register

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

typedef struct ctrl_reg
{
    uint16_t Mode :3;
    uint16_t Speed :5;
    uint16_t Reserved :2;
    uint16_t Status :6;
}stCtrlReg_t;

uint16_t pack_register(uint8_t mode, uint8_t speed, uint8_t status) {
    stCtrlReg_t ctrl_reg;
    ctrl_reg.Mode = mode;
    ctrl_reg.Speed = speed;
    ctrl_reg.Status = status;
    // Your logic here
    return *((uint16_t *)&ctrl_reg);
}

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;
}