#include <bits/stdc++.h>
using namespace std;
int main() {
  char input[100 + 1];
  char result[(100 << 1) + 1];
  scanf("%s", input);
  int index = 0;
  for (int i = 0; input[i]; ++i) {
    char c = tolower(input[i]);
    if (c == 'a' || c == 'e' || c == 'i' || c == 'o' || c == 'u' || c == 'y') {
      continue;
    } else {
      result[index++] = '.';
      result[index++] = c;
    }
  }
  result[index] = '\0';
  cout << result << endl;
  return 0;
}
