#include<stdio.h>   
FILE *f,*g;   
int main()   
{   
f=fopen("fact.in","r");   
g=fopen("fact.out","w");   
long int p,s=1,i;   
int a[50000];   
fscanf(f,"%ld",&p);   
if(p==0)      {         i=1; fprintf(g,"%ld",i);      }   
 else if(p<0) {           i=-1; fprintf(g,"%ld",i);   }   
 else {    
        s=p*5;      
        fprintf(f,"%ld",s);     
      }         
return 0;   
}