package chelper;

import java.util.Arrays;

import io.InputReader;
import io.OutputWriter;

public class TaskI {

  public static final int MAGIC_KEK = 1000000;

  public void solve(int testNumber, InputReader in, OutputWriter out) {
    int n = in.nextInt();
    String[] strings = new String[n];

    for (int i = 0; i < n; i++) {
      strings[i] = in.nextString();
    }

    String e = in.nextString();

    int m = e.length();

    int[] dp = new int[m + 1];

    Arrays.fill(dp, MAGIC_KEK);

    dp[0] = 0;

    for (int i = 0; i < n; i++) {
      for (int j = 0; j < strings[i].length(); j++) {
        int c = 0;
        for (int k = 0; j + k < strings[i].length() && c < e.length(); k++) {
          if (strings[i].charAt(j + k) == e.charAt(c)) {
            c++;
            dp[c] = Math.max(dp[c], 1);
          }
        }
      }
    }

    for (int i = 0; i < m; i++) {
      for (int j = 0; j < n; j++) {
        int c = 0;
        for (int k = 0; i + c < e.length() && k < strings[j].length(); k++) {
          if (strings[j].charAt(k) == e.charAt(i + c)) {
            c++;
            dp[i + c] = Math.min(dp[i + c], dp[i] + 1);
          }
        }
      }
    }

    if (dp[m] >= MAGIC_KEK) {
      out.println(-1);
    } else {

      out.println(dp[m]);
    }
  }
}