Decision Making and Branching

An electric power distribution company charges its domestic consumers as follows:
Consumption Units     Rate of Charge
    0 - 200                         Rs. 0.50 per unit
201 - 400                         Rs. 100 plus Rs. 0.65 per unit excess of 200
401 - 600                         Rs. 230 plus Rs. 0.80 per unit excess of 400
601 and above                Rs. 390 plus Rs. 1.00 per unit excess of 600
This program reads the customer number and power consumed and prints the amount to be paid by the customer.

#include <stdio.h>
void main()
{
int  units, custnum;
float charges;
printf("Enter CUSTOMER NO. and UNITS consumed\n");
scanf("%d %d", &custnum, &units);
if (units <= 200)
charges = 0.5 * units;
else if (units <= 400)
charges = 100 + 0.65 * (units - 200);                   else if (units <= 600)
charges = 230 + 0.8 * (units - 400);
else
charges = 390 + (units - 600);
printf("\n\nCustomer No: %d: Charges = %.2f\n",
custnum, charges);
getch();
}