#include <bits/stdc++.h> using namespace std;
int main() { double a,b; cin>>a; if(a<=1000) { b=a*0.95; cout<<fixed<<setprecision(2)<<b; } else {

   b=(a-1000)*0.9+1000*0.95;
   cout<<fixed<<setprecision(2)<<b;	
}

return 0;}

#include using namespace std; int main() { float a,b; scanf("%f",&a); if(a<=1000) b=0.95a; else b=10000.95+(a-1000)*0.9; printf("%.2f\n",b); return 0; }