#include <bits/stdc++.h>

using namespace std;

int main()
{
    string v;
    int t;
    cin>>v>>t;
    int s=0;
    for(int ctr1=2;ctr1<6;ctr1++){
        s*=10;
        s+=v[ctr1]-'0';
    }
    cout<<(s*t)/10000;
    return 0;
}