#include <bits/stdc++.h>
using namespace std;
int main() {
  char str[105];
  while (scanf("%s", str) == 1) {
    int i = 0, f = 0;
    while (str[i]) {
      if (str[i] <= 'Z') str[i] += 32;
      if (str[i] != 'a' && str[i] != 'e' && str[i] != 'i' && str[i] != 'y' &&
          str[i] != 'o' && str[i] != 'u')
        f = 1, printf(".%c", str[i]);
      ++i;
    }
    if (f) puts("");
  }
  return 0;
}
