import java.util.Scanner;

// 注意类名必须为 Main, 不要有任何 package xxx 信息
public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        // 注意 hasNext 和 hasNextLine 的区别
        while (in.hasNext()) { // 注意 while 处理多个 case
            String a = in.next();
            String b = in.next();
            if(a.length() > b.length()){
                zichuan(b,a);
            }else{
                zichuan(a,b);
            }
            
        }
    }
    public static void zichuan(String s1, String s2) {
        //i代表子串长度
        for (int i = s1.length(); i > 0; i--) { //遍历每个子串长度
            //遍历s1
            for (int j = 0; j < s1.length() + 1 - i; j++) {
                if (s2.contains(s1.substring(j, j + i))) {
                    System.out.print(s1.substring(j, j + i));
                    return;
                }
            }
        }
    }
}