#include <bits/stdc++.h>   using namespace std;   int main() {     string s;     cin >> s;     int len = s.size();     cout << s[0];     int flag = 0;     for (int i = 1; i < len; i++) {       if (s[i] ==  d  && s[i + 1] ==  o  && s[i + 2] ==  t  &&           (i + 2 != len - 1)) {         cout <<  . ;         i += 2;       } else if (s[i] ==  a  && s[i + 1] ==  t  && flag == 0) {         cout <<  @ ;         i++;         flag = 1;       } else         cout << s[i];     }   }   