# Factorial

The factorial of an integer

`n`

is defined as the product of all the integers from `1`

up to `n`

.Write a program that given a single integer

`n`

, would print the result of `n!`

in the output.Input | Output |

1 | 1 |

5 | 120 |

0 | 1 |

#### Constraints

Time limit: 1 seconds

Memory limit: 512 MB

Output limit: 1 MB