#include <bits/stdc++.h>
using namespace std;
int n;
string str;
bool diverse;
int main() {
  cin >> n;
  for (int i = 1; i <= n; i++) {
    diverse = true;
    cin >> str;
    for (int i = 0; i < str.length() - 1; i++) {
      for (int j = 0; j < str.length() - 1; j++) {
        if (str[j] > str[j + 1]) {
          swap(str[j], str[j + 1]);
        }
      }
    }
    for (int i = 0; i < str.length() - 1; i++) {
      if (int(str[i + 1]) - int(str[i]) != 1) {
        diverse = false;
      }
    }
    if (diverse)
      cout << "yes" << endl;
    else
      cout << "no" << endl;
  }
}
