27. Extract Bit Field from 16-bit Register

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

uint8_t extract_field(uint16_t reg) 
{
    uint16_t result = 0,leftSftIndex=0;
    for(uint8_t index=4;index<=8;index++)
    {
       result |= ((reg >> index)&0x0001) << leftSftIndex;
       leftSftIndex++;
    }
    return result;
}

int main() {
    uint16_t reg;
    scanf("%hx", &reg);
    printf("%u", extract_field(reg));
    return 0;
}