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

#include <stdio.h>
#include <stdint.h>
#define MODE_MASK ~7
#define SPEED_MASK ~(31<<3)
#define STATUS_MASK ~(63<<10)
uint16_t pack_register(uint8_t mode, uint8_t speed, uint8_t status) {
    // Your logic here
    uint16_t pack_reg = 0;
    pack_reg |= (pack_reg&MODE_MASK)|mode;
    pack_reg |= (pack_reg&SPEED_MASK)|(speed<<3);
    pack_reg |= (pack_reg&STATUS_MASK)|(status<<10);
    return pack_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;
}