#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;

int main(){
   double a ,b;
   cin >> a >> b;

   double ans = a*b;

 
   cout << ans/100 << endl;

}
#include<bits/stdc++.h>
using namespace std;

//My typenames
typedef long long l1;
typedef vector<int> vi;
typedef vector<l1> vl;
typedef pair<int,int> pi;
typedef map<int,int> mp;

//My Macros
#define F first
#define S second
#define pushb push_back
#define popb pop_back
#define fli(i,a,b) for(int i=a;i<b;i++)
#define fld(i,a,b) for(int i=a;i>b;i--)


void solve(){
    float a,b;
    cin>>a>>b;
    cout<<(float)(b/100.0)*a<<"\n";
}

int main()
{
    ios::sync_with_stdio(0);
    cin.tie(0);

    //freopen("in","r",stdin);
    //freopen("out","w",stdout);

    //Getting test cases
    solve();

    return 0;
}