Factorial of a number in Ruby

1. A.Factorials are very simple things. They're just products, indicated by an exclamation mark. For instance, "four factorial" is written as "4!" and means 1×2×3×4 = 24. In general, n! ("n factorial") means the product of all the whole numbers from 1 to n; that is, n! = 1×2×3×...×n.
2. Factorial of a number in Ruby

#!/usr/bin/ruby

puts "Enter a Number"

n=gets.to_i

fact=1

for i in 1..n

fact=fact*i

end

puts fact.

Out put:

Enter a Number

5

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