当输入 < 0 并且最低税率相同时，如何使代码停止，然后打印出以下国家/地区

Question

How can I make the code stop when the input<0 and when the lowest tax is the same. I have 4 countries and for example if Denmark and Norway have the same tax it will print out: "Denmark Norway" in alphabetical row. Here is an example: Income: 1000000 Lowest tax: 150000.0 USA
Income: 6000 Lowest tax: 1500.0 Denmark Norway USA
Income: -1

Here is my code, it prints out the lowest value and it's country:

`

continue_input = True
income = 0

while continue_input and income >= 0:
    income = int(input('Income: '))

    # Canada   
    canada_tax = 0.26
    canada = canada_tax * income

    # Norway
    if income > 3000:
        norway_tax1 = 0.1 * 3000
        tax_left = income - 3000
        norway_tax2 = 0.4 * tax_left
        norway_tax = norway_tax1 + norway_tax2
    elif income < 3000:
        norway_tax = 0.1 * income

    # Denmark
    denmark_tax = 0
    percent = 0
    for _ in range(int(income/1000)):
      denmark_tax += percent * 1000
      percent += 0.1
      denmark_tax += percent * (income%1000)
      
    # USA
    if income <= 1500:
        USA_tax = 0.12 * income
    elif income > 1500 and income <= 6000:
        USA_tax = 0.25 * income
    elif income > 6000 and income <= 10000:
        USA_tax = 0.38 * income
    elif income > 10000:
        USA_tax = 0.15 * income



    #Print lowest tax
    if canada < norway_tax and canada < USA_tax and canada < denmark_tax:
        print(f'Lowest tax: {canada}')
        print('Canada')
    elif norway_tax < canada and norway_tax < USA_tax and norway_tax < denmark_tax:
        print(f'Lowest tax: {norway_tax}')
        print('Norway')
    elif USA_tax < canada and USA_tax < norway_tax and USA_tax < denmark_tax:
        print(f'Lowest tax: {USA_tax}')
        print('USA')
    elif denmark_tax < canada and denmark_tax < norway_tax and denmark_tax < USA_tax:
        print(f'Lowest tax: {denmark_tax}')
        print('Denmark')

I'm expecting this:

Income: 1000000
Lowest tax: 150000.0
USA
Income: 6000
Lowest tax: 1500.0
Denmark Norway USA
Income: -1

Answer 1

Since, you are taking the input inside the while loop, It will first execute all the calculations, then print and then check if income is less than 0 or not.

To avoid this you can remove income>=0 condition from the while loop and instantly check if the value is negative or not. Also your code will not print if more than 1 country has minimum tax because you are only checking for less value and not equal.

A simple and easy way of solving both the above problem can be:-

continue_input = True
income = 0

# changed here
while continue_input :
    income = int(input('Income: '))

    # changed here
    if income < 0 :
        break

    # Canada   
    canada_tax = 0.26
    canada = canada_tax * income

    # Norway
    if income > 3000:
        norway_tax1 = 0.1 * 3000
        tax_left = income - 3000
        norway_tax2 = 0.4 * tax_left
        norway_tax = norway_tax1 + norway_tax2
    elif income < 3000:
        norway_tax = 0.1 * income

    # Denmark
    denmark_tax = 0
    percent = 0
    for _ in range(int(income/1000)):
      denmark_tax += percent * 1000
      percent += 0.1
      denmark_tax += percent * (income%1000)
      
    # USA
    if income <= 1500:
        USA_tax = 0.12 * income
    elif income > 1500 and income <= 6000:
        USA_tax = 0.25 * income
    elif income > 6000 and income <= 10000:
        USA_tax = 0.38 * income
    elif income > 10000:
        USA_tax = 0.15 * income
        

    # changed here
    min_tax = min(canada, norway_tax, USA_tax, denmark_tax)
    print(f'Lowest tax: {min_tax}', end = " ")

    if min_tax == canada :
        print('Canada', end = " ")

    if min_tax == denmark_tax :
        print('Denmark', end = " ")

    if min_tax == norway_tax :
        print('Norway', end = " ")

    if min_tax == USA_tax :
        print('USA',end= " ")
    print()

output:-

 Income: 1000000 Lowest tax: 150000.0 USA Income: 6000 Lowest tax: 1500.0 Denmark Norway USA Income: -1

PS:- I tweaked the print statements using end = " " so that you can get the output in desired form. I have also commented before I have made changes in the code