Electric Bill Calculator

#include <stdio.h>

int main()
{
    float units, sc=100, vat=15, bill;  // sc = service charge, vat 15% if total bill is more than 400.

    printf("Please give your Used Electric Units\n");

    scanf("%f", &units);

    if(units >= 0 && units <= 200){
        bill = (units*0.8)+sc;
    } else if(units > 200 && units <= 300){
        bill = (units*0.9)+sc;
    } else {
        bill = (units*1)+sc;
    }

    if(bill >= 400){
        bill = bill + (bill*(vat/100));
    }

    printf("Your Total Payable Bill is %.2f Tk.", bill);

    return 0;
}