#include<iostream> #include<string> #include<string.h> #include<algorithm> #include<stdio.h> #include<cmath> #include<vector> #include<utility> #include<stack> #include<queue> #include<list> #include<bitset> #include<functional> #define FOR(i, a, b) for(int i=(a);i<=(b);i++) #define RFOR(i, a, b) for(int i=(a);i>=(b);i--) #define MOD 1000000007 #define INF 1000000000 #define PI 3.14159265358979 using namespace std; typedef pair<int, int> P; int main(void) { string s; int v = 0; int t; int p; int i = 0; cin >> s >> t; while (1) { if (s[i] == '.') { FOR(u, 0, 3) { v += (s[i + 4 - u] - '0')*pow(10, u); } break; } i++; } cout << v*t / 10e3 << endl; return 0; }