19. Extract a Bit Field from a 32-bit Register

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

uint32_t extract_field(uint32_t reg, uint8_t pos, uint8_t len) {
    // Your code here
    uint32_t extracted_val;
    uint64_t mask;
    
    mask = (uint64_t)((1ULL << len) - 1ULL);
    extracted_val = (uint32_t)((reg >> pos) & (mask));
    
    return extracted_val;
}

int main() {
    uint32_t reg;
    uint8_t pos, len;
    scanf("%u %hhu %hhu", &reg, &pos, &len);
    printf("%u", extract_field(reg, pos, len));
    return 0;
}