Write a program "lab$2$Problem$2.$c$"$ to calculate the permutation and combination for

given $n$ and $r.$ The values of $n$ and $r$ should be passed to the program as a command$-$

line argument. The permutation and combination are defined for given $n$ and $r$ as:

$P(n,r)=\frac{n!}{(n-r)!},C(n,r)=\frac{P(n,r)}{r!}$

Output Format:

$P(5,3)=60$

$C(5,3)=10$

Requirement:

The program should take $2$ command$-$line arguments. First argument

should be the value of $n$ and the second argument should be the value of $r.$

First create a factorial function. Then, you can use the factorial function in

the functions to compute permutation and combination.

The result should be printed in the main function.

Sample Run:

$($base$)$ jovyanejupyter$-$asainju: $/3240/1$ab$2$$ gcc $1$ab$2$Problem$2,$c $-$o $1$ab$2$Problem$2$

$($base$)$ jovyanejupyter$-$asainju: $/3240/1$ab$2$$$./1$ab$2$Problem$253$

$P(5,3)=60$

$c(5,3)=10$

$($base$)$ jovyanejupyter$-$asainju: $/3240/1$ab$2$$$./1$ab$2$Problem$2205$

$P(20,5)=1860480$

$c(20,5)=15504$