// Checker for problem K
// Author: Adam Polak

#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

const int N = 26;

bool ok[N][N];
char solution[50][50];

int main(int argc, char* argv[]) {
  FILE* in = fopen(argv[1], "r");
  FILE* hint = fopen(argv[2], "r");
  FILE* out = fopen(argv[3], "r");

  int Z;
  fscanf(in, "%d", &Z);
  while (Z--) {
    int n;
    fscanf(in, "%d", &n);

    for (int i = 0; i < N; ++i)
      for (int j = 0; j < N; ++j)
        ok[i][j] = true;

    while (n--) {
      char w[4];
      fscanf(in, "%s", w);
      ok[w[0]-'a'][w[1]-'a'] = false;
    }

    char buf[50];
    fscanf(hint, "%s", buf);
    int m = strlen(buf);
    for (int i = 1; i < m; ++i)
      fscanf(hint, "%s", buf);
    for (int i = 0; i < m; ++i) {
      assert(fgets(buf, 50, out) != NULL);
      assert(strlen(buf) == m + 1);  // +1 for end-of-line
      for (int j = 0; j < m; ++j)
        solution[i][j] = buf[j] - 'a';
    }
    for (int i = 0; i < m; ++i)
      for (int j = 0; j < m - 1; ++j)
        assert(ok[solution[i][j]][solution[i][j+1]]);
    for (int i = 0; i < m - 1; ++i)
      for (int j = 0; j < m; ++j)
        assert(ok[solution[i][j]][solution[i+1][j]]);
  }
  printf("OK\n");
  return 0;
}