PROGRAMMING:Seeking factorial

This topic requires reading in any non negative integer n and outputting the factorial of n.
###Input format:
Enter any integer n.
###Output format:
Outputs the value of the factorial of n.
###Input example:
Here is a set of inputs. For example:
```in
five
```
###Output example:
The corresponding output is given here. For example:
```out
one hundred and twenty
```







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