#include <bits/stdc++.h>
using namespace std;
const int N = 105;
int n;
char s[2 * N];
int main() {
  int T;
  scanf("%d", &T);
  while (T--) {
    for (int i = 1; i <= 200; i++) s[i] = (i % 26 ? i % 26 : 26) + 'a' - 1;
    scanf("%d", &n);
    for (int i = 1; i <= 200; i++) printf("%c", s[i]);
    printf("\n");
    for (int i = 1; i <= n; i++) {
      int x;
      scanf("%d", &x);
      x++;
      s[x] = (s[x] + 1) > 'z' ? 'a' : s[x] + 1;
      for (int j = 1; j <= 200; j++) {
        printf("%c", s[j]);
      }
      printf("\n");
    }
  }
  return 0;
}
