#include <bits/stdc++.h>
using namespace std;
int main() {
  string p;
  cin >> p;
  for (int i = 0; i < p.length(); i++) {
    if (p[i] != 'a' && p[i] != 'e' && p[i] != 'i' && p[i] != 'o' &&
        p[i] != 'u' && p[i] != 'y' && p[i] != 'A' && p[i] != 'E' &&
        p[i] != 'I' && p[i] != 'O' && p[i] != 'U' && p[i] != 'Y') {
      cout << ".";
      putchar(tolower(p[i]));
    }
  }
}
