Java 代码

import java.util.Scanner;

public class Main
{
    public static void main(String[] args)
    {
        Scanner cin = new Scanner(System.in);

        int n = cin.nextInt();

        while ( n > 0)
        {
            String[] s = new String[n];
            int min_len = 200;

            for (int i = 0; i < n; i ++)
            {
                s[i] = cin.next();
                if (min_len > s[i].length())
                    min_len = s[i].length();
            }

            boolean is_success = true; 
            for (int j = 0; j < min_len; j ++)
            {
                char c = s[0].charAt(s[0].length() - 1 - j);
                for (int k = 1; k < s.length; k ++)
                {
                    if (c != s[k].charAt(s[k].length() - 1 - j)) 
                    {
                        is_success = false;
                        break;
                    }
                }

                if (!is_success)
                {
                    System.out.println (s[0].substring(s[0].length() - j));
                    break;
                }
            }

            if (is_success)
                    System.out.println (s[0].substring(s[0].length() - min_len));

            n = cin.nextInt();
        }
    }
}