#include <bits/stdc++.h>
using namespace std;
char x[101];
char y[101];
int main() {
  cin >> x;
  int j = 0, i = 0;
  while (x[i] != '\0') {
    if (x[i] == 'a' || x[i] == 'A' || x[i] == 'o' || x[i] == 'O' ||
        x[i] == 'y' || x[i] == 'Y' || x[i] == 'e' || x[i] == 'E' ||
        x[i] == 'u' || x[i] == 'U' || x[i] == 'i' || x[i] == 'I') {
      i++;
      continue;
    }
    if (x[i] > 'A' && x[i] <= 'Z') x[i] += 32;
    y[j++] = '.';
    y[j++] = x[i];
    i++;
  }
  y[j] = '\0';
  cout << y << endl;
  return 0;
}
