// An electricity provider charges the
// following rates for monthly consumption:
//
//     Consumption        Rate
//    First 100 kWh     $0.10/kWh
//     Next 200 kWh     $0.15/kWh
//    Above 300 kWh     $0.20/kWh
//
// Given a nonnegative integer consumption,
// calculate and print the total bill.
// Each rate applies only to the electricity
// consumed within its corresponding tier.
//
// For example, a household consuming
// 340 kWh pays for
//   100 kWh at $0.10, so 10.00
//   200 kWh at $0.15, so 30.00
//    40 kWh at $0.20, so  8.00
// for a total of $48.00
//
// Display "Invalid consumption." if the
// number is negative and return -1.
//
// Instead of using floating-point numbers,
// use integers and calculate the number of
// cents that must be paid. To display the 
// amount owed:
//   1. Print the string "$".
//   2. Print the total divided by 100.
//   3. Print a ".".
//   4. Determine the remainder modulo 100:
//       a. If the remainder is 0, print "00".
//       b. If the remainder is less than ten,
//             print a "0" and the remainder.
//       c. Otherwise, print the remainder.

// All values will be integers, including the
// number of kilowatt-hours and the prices
// in cents. This avoids round-off errors.
//
// Note: a watt is a joule per second, and
// an hour is 3600 seconds. Thus a 
// kilowatt-hour or kWh is
//     1000 J/s x 3600 s = 3 600 000 J, 
// or
//     3.6 MJ.
//
// Why do we not just charge per MJ? Electrical
// energy has traditionally been measured in
// kilowatt-hours because this unit relates
// energy consumption directly to electrical
// power and time. For example, if you leave
// a 100 W light bulb running for one hour,
// it consumes 0.1 kWh.

// Function declarations
int main();

// Function definitions
int main() {
    // Query the user for a nonnegative integer
    // number of kilowatt-hours and assign it to
    // 'consumption'.

    return 0;
}