func_code_string: #include <bits/stdc++.h>   using namespace std;   int main() {     double weight = 0;     long n, m;     cin >> n >> m;     long long a[n];     long long b[n];     bool flag = 0;     for (long i = 0; i < n; i++) {       cin >> a[i];       if (a[i] == 1) {         flag = 1;       }     }     for (long i = 0; i < n; i++) {       cin >> b[i];       if (b[i] == 1) {         flag = 1;       }     }     if (flag == 1) {       cout << -1 << endl;       exit(0);     }     weight = m;     weight += double(weight) / double(b[0] - 1);     for (long i = n - 1; i > 0; i--) {       weight += double(weight) / double(a[i] - 1);       weight += double(weight) / double(b[i] - 1);     }     weight += double(weight) / double(a[0] - 1);     cout << setprecision(30) << weight - m << endl;   }   