#include <bits/stdc++.h>
using namespace std;
int main() {
  char arr[105];
  cin >> arr;
  int s2 = strlen(arr);
  for (int j = 0; j < s2; j++) {
    arr[j] = tolower(arr[j]);
    if (arr[j] == 'a' || arr[j] == 'o' || arr[j] == 'e' || arr[j] == 'u' ||
        arr[j] == 'i' || arr[j] == 'y') {
      continue;
    } else {
      cout << "." << arr[j];
    }
  }
  return 0;
}
