#include <bits/stdc++.h>
using namespace std;
char a[10001];
int main() {
  scanf("%s", a + 1);
  int l = strlen(a + 1);
  for (int i = 1; i <= l; i++) {
    if ((a[i] == 'A') || (a[i] == 'E') || (a[i] == 'I') || (a[i] == 'O') ||
        (a[i] == 'U') || (a[i] == 'Y') || (a[i] == 'a') || (a[i] == 'e') ||
        (a[i] == 'i') || (a[i] == 'o') || (a[i] == 'u') || (a[i] == 'y'))
      ;
    else {
      if (a[i] <= 'Z') a[i] += 32;
      printf(".%c", a[i]);
    }
  }
  return ~~(0 - 0);
}
