Extract a Bit Field from a 32-bit Register

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

   
uint8_t extract_field(uint32_t reg, uint8_t pos, uint8_t len) {
    uint8_t value = (reg >> pos) & ((1 << len) - 1);
    return value;
} // 1 << len - 1 tworzy maskę dla ilosci bitów np. 0001 0000 - 1 = 0000 1111


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;
}