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https://github.com/TheAlgorithms/Ruby
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39 lines
976 B
Ruby
39 lines
976 B
Ruby
# A ruby program to find factorial of a given integer
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# Factorial of a given integer is defined as the product of all the positive integers less than or equal to the given integer
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# Mathematical representation: n! = n * (n - 1) * (n - 2) * ... * 1
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def factorial(number)
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input = number
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factorial = 1
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if number < 0
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"Please check your input number! The given number is a negative number."
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else
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while number > 0
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factorial *= number
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number -= 1
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end
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"The factorial of #{input} is #{factorial}."
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end
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rescue
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"Error: Please provide integer only!"
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end
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# Valid inputs
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puts factorial(0)
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# The factorial of 0 is 1.
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puts factorial(10)
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# The factorial of 10 is 3628800.
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puts factorial(1)
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# The factorial of 1 is 1.
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puts factorial(-5)
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# Please check your input number! The given number is a negative number.
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# Invalid inputs
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puts factorial("a")
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# Error: Please provide integer only!
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puts factorial("2")
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# Error: Please provide integer only!
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