func_code_string: #include <bits/stdc++.h>   using namespace std;   const int MAX = 1e7;   int n;   int m[100], r[100];   bool am[MAX];   int main() {     ios_base::sync_with_stdio(false);     cin.tie(0);     cin >> n;     for (int i = 1; i <= n; i++) cin >> m[i];     for (int i = 1; i <= n; i++) cin >> r[i];     for (int i = 1; i <= n; i++) {       bool da = 0;       for (int k = 0; k * m[i] + r[i] < MAX; k++) am[k * m[i] + r[i]] = 1;     }     int cnt = 0;     for (int i = 1; i < MAX; i++) cnt += am[i];     cout << 1.00 * cnt / (MAX - 1);     return 0;   }   