Extract the Nibble from an 8-bit Register

Code

#include <stdio.h>

unsigned char extractNibble(unsigned char reg, int pos) {
    // Write your code here
    int res;
    if( pos ==1  ){
        res  |= (( reg >> 4 ) & 0xF );
    }else{
         res  |= (0xF & reg  );
    }
    return res;
}

int main() {
    unsigned char reg;
    int pos;
    scanf("%hhu %d", &reg, &pos);
    printf("%d", extractNibble(reg, pos));
    return 0;
}

Solving Approach