#include<bits/stdc++.h>
using namespace std;
using ll=long long int;
int main()
{
  ios::sync_with_stdio(false);
  cin.tie(NULL);
  float a=0,b=0;
  cin >> a >> b;
  float ans=0.0;
  if(b!=0)
  {
    ans=(a*b)/100;
    cout <<  ans << "\n";
  }
  else
  {
    cout << "0" << "\n";
  }
  return 0;
}
#include <bits/stdc++.h>
using namespace std;
#define _GLIBCXX_DEBUG
#define rep(i,n) for (int i=0;i<n;i++)
#define INF 1000000001
#define lINF 1000000000000001
using ll = long long;
using vi = vector<int>;
using vll = vector<ll>;
using vvll = vector<vll>;
using ii = pair<int, int>;
using vvi = vector<vi>;
using vii = vector<ii>;
using vs = vector<string>;
using vc = vector<char>;
using P = pair<ll, ll>;
using si = stack<int>;
using ss = stack<string>;
ll gcd(ll a, ll b) { return b?gcd(b,a%b):a;}
ll lcm(ll a, ll b) { return a/gcd(a,b)*b;}
//1e9<int型の最大値<1e10
//1e18<long型の最大値<1e19
//配列直入れ↓
//g++ -std=c++17 -Wshadow -Wall -D_GLIBCXX_DEBUG -o a b.cpp && ./a
//bit全探索
//2のk乗は"1<<k"で書ける


int main(){
    float a,b;
    cin>>a>>b;
    cout<<a/100*b<<endl;

}