// Timus 1020
#include "iostream.h"
#include "math.h"

void main()
{
  int i,n;
  double r,L,x[100],y[100];
  cin>>n>>r;
  for (i=1;i<=n;i++)
  { cin>>x[i]>>y[i];}
  x[0]=x[n]; y[0]=y[n];
  L=0;
  for (i=0;i<n;i++)
  { L+=(sqrt(pow(x[i]-x[i+1],2)+pow(y[i]-y[i+1],2)));
  }
  L+=2*r*M_PI;
  cout.precision(2);
  cout<<L;
}

> // Timus 1020
> #include "iostream.h"
> #include "math.h"
>
> void main()
> {
>   int i,n;
>   double r,L,x[100],y[100];
>   cin>>n>>r;
>   for (i=1;i<=n;i++)
>   { cin>>x[i]>>y[i];}
>   x[0]=x[n]; y[0]=y[n];
>   L=0;
>   for (i=0;i<n;i++)
>   { L+=(sqrt(pow(x[i]-x[i+1],2)+pow(y[i]-y[i+1],2)));
>   }
>   L+=2*r*M_PI;
>   cout.precision(2);
>   cout<<L;
> }
>

Thanks.
But there isn't this problem.