#include <bits/stdc++.h>   using namespace std;   const int INF = 1e9 + 7;   const int N = 1e4 + 10;   int main() {     string str;     cin >> str;     cout << str[0];     int flag = 0;     for (int i = 1; i < str.length(); i++) {       if (!(i + 2 >= str.length() || flag == 1)) {         if (str.substr(i, 2) ==  at ) {           cout <<  @ ;           i++;           flag = 1;           continue;         }       }       if (i + 3 < str.length()) {         if (str.substr(i, 3) ==  dot ) {           cout <<  . ;           i += 2;           continue;         }       }       cout << str[i];     }     return 0;   }   