/*#include <stdio.h>
int n;
long long int f(int x)
{
long long int s=0;
for(x=0;x<=n;x=x+1)
{
s=s+x;
}
return s;
}
int main()
{
scanf("%d", &n);
printf("%lld\n", f(n));
}
*/
/*#include <stdio.h>
int n;
int f(int p)
{
int s=0;
for(p=1;p<=n;p=p+1)
{
if(n%p==0)
{
s=s+1;
}
}
return s;
}
int main()
{
scanf("%d", &n);
printf("%d\n", f(n));
}
*/
/*#include <stdio.h>
float circle(int r)
{
float s;
s=3.14*r*r;
return s;
}
main()
{
int r;
scanf("%d", &r);
printf("%.2f", circle(r));
}
*/