# Compute the amount of federal income tax payable

# Use constants for the tax bracket limits and the tax rates so that it
# is easy to update the program when these values change.
LIMIT_1 = 43561
LIMIT_2 = 87123
LIMIT_3 = 135054

RATE_1 = 0.15
RATE_2 = 0.22
RATE_3 = 0.26
RATE_4 = 0.29

# Read the user's income
income = float(input("Enter your income: "))

# Compute the amount of tax owing if the user's income is in the lowest bracket
if income < LIMIT_1:
  tax = RATE_1 * income
# Compute the amount of tax owing if the user's income is in the second bracket
elif income < LIMIT_2:
  tax = RATE_1 * LIMIT_1 + RATE_2 * (income - LIMIT_1)
# Compute the amount of tax owing if the user's income is in the third bracket
elif income < LIMIT_3:
  # The \ character at the end of a line is the "line continuation character".
  # It allows you to continue your expression on the next line.  The \ must
  # be the last character on the line without any spaces after it.
  tax = RATE_1 * LIMIT_1 + RATE_2 * (LIMIT_2 - LIMIT_1) + \
        RATE_3 * (income - LIMIT_2)
# Compute the amount of tax owing if the user's income is in the highest bracket
else:
  tax = RATE_1 * LIMIT_1 + RATE_2 * (LIMIT_2 - LIMIT_1) + \
        RATE_3 * (LIMIT_3 - LIMIT_2) + RATE_4 * (income - LIMIT_3)

# Display the result formatted so that it has two digits to the right of
# the decimal point.
print("Your tax payable is $%.2f." % tax)