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 new_reg = 0;
    for(int i=len-1 ; i>=0;  i--){
         new_reg |= (0x01 << i);
    }
    new_reg = (new_reg << pos);
    reg = reg & new_reg;
    reg = reg >> pos;
    return reg;
}

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;
}