exercism.org/python/currency-exchange/HINTS.md

Hints

General

• The Python Numbers Tutorial and Python numeric types can be a great introduction.

1. Estimate value after exchange

• You can use the division operator to get the value of exchanged currency.

2. Calculate currency left after an exchange

• You can use the subtraction operator to get the amount of change.

3. Calculate value of bills

• You can use the multiplication operator to get the value of bills.

4. Calculate number of bills

• You need to divide amount into denomination.

• You need to use type casting to int to get the exact number of bills.

• To remove decimal places from a float, you can convert it to int.

  Note: The // operator also does floor division. But, if the operand has float, the result is still float.

5. Calculate leftover after exchanging into bills

• You need to find the remainder of amount that does not equal a whole denomination.
• The Modulo operator % can help find the remainder.

6. Calculate value after exchange

• You need to calculate spread percent of exchange_rate using multiplication operator and add it to exchange_rate to get the exchanged currency.
• The actual rate needs to be computed. Remember to add exchange rate and exchange fee.
• You can get exchanged money affected by commission by using divide operation and type casting to int.