int FUN (int n) 
 {{ 
 if (n == 0 || n == 1) 
 Return 1; 
 else if (n> 0) 
 Return n * fun (n -1); 

 } 
 int Main () 
 {{ 
 int n; 
 scanf ("%d", & n); 
 if (n <0) 
 Printf ("given <0, no value! no value!"); 
 else 
 Printf ("%d! =%d", n, fun (n)); 
 Return 0; 
 }

Input format:

Enter the value of an arbitrary integer n.

output format:

If n = 0 or n = 1, then n! = 1; if n <0, output the “given number <0, no value! No value!”.

Input sample:

Here gives a set of inputs. For example:

5

output sample:

Here gives the corresponding output. For example:

5!=120