28 lines
625 B
Python
28 lines
625 B
Python
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# Lesson 2 Task 3: display all numbers from n to 1, then remove the first number and repeat while n > 0
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# Author: Stanislav Mykhailenko
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# License: Unlicense
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# Return codes:
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# 0 - OK
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# 1 - Invalid number entered
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import math, sys
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def numberError():
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print("Invalid number entered.")
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sys.exit(1)
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try: number = int(input("Enter a natural number: "))
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except ValueError: numberError()
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if number < 1: numberError()
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while number > 0:
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currentNumber = number
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while currentNumber > 0:
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print(currentNumber, end='')
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if currentNumber > 1: print(' ', end='')
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currentNumber = currentNumber - 1
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print('')
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number = number - 1
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