#include <bits/stdc++.h>
using namespace std;
int main() {
  ios_base ::sync_with_stdio(0);
  cin.tie(0);
  ;
  long long int t;
  cin >> t;
  while (t--) {
    string s;
    cin >> s;
    long long int a[26] = {0};
    long long int cnt = 0;
    char c;
    int i = 0;
    while (i < s.length()) {
      cnt = 0;
      c = s[i];
      while (s[i] == c && i < s.length()) {
        cnt++;
        i++;
      }
      if (cnt % 2 != 0) {
        a[c - 'a'] = 1;
      }
    }
    string ans = "";
    for (i = 0; i < 26; i++) {
      if (a[i] == 1) {
        ans += (i + 'a');
      }
    }
    cout << ans << endl;
  }
}
