#include<bits/stdc++.h>
using namespace std;
int main(void)
{
    int l;
    scanf("%d",&l);
    if(l<=100000)printf("%g",0.1*l);
    else if(l>100000&&l<=200000)printf("%g",(0.1*100000+0.075*(l-100000)));
    else if(l>200000&&l<=400000)printf("%g",(0.1*100000+0.075*(100000)+0.05*(l-200000)));
    else if(l>400000&&l<=600000)printf("%g",(0.1*100000+0.075*(100000)+0.05*(200000)+0.03*(l-400000)));
    else if(l>600000&&l<=1000000)printf("%g",(0.1*100000+0.075*(100000)+0.05*(200000)+0.03*(200000)+0.015*(l-600000)));
    else 
        printf("%g",(0.1*100000+0.075*(100000)+0.05*(200000)+0.03*(200000)+0.015*(400000)+0.01*(l-1000000)));
    return 0;
}