Extract a Bit Field from a 32-bit Register

Code

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

uint32_t extract_field(uint32_t reg, uint8_t pos, uint8_t len) {
    // Your code here
    uint32_t mask = 0;
    uint32_t x = 0;
    
    if (reg == 0x00) return 0;

    while(x < len)
    {
        // to know if it is 1
        if (reg & (1 << (pos + x)))
        {
            mask |= (1 << x);
        }
        x++;
    }
    return mask;
}

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;
}

Solving Approach