import java.util.*;
import java.io.*;
public class homework {
	static BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
	static PrintWriter pr = new PrintWriter(new BufferedWriter(new OutputStreamWriter(System.out)));
	static StringTokenizer st;
	public static void main(String[] args) throws IOException {
		String s1 = next(), s2 = next();
		long hash1[] = new long[s1.length()+1], hash2[] = new long[s2.length()+1];
		long pow[] = new long[s1.length()+1], base = 131;
		pow[0] = 1;
		for(int i=1; i<=s1.length(); i++) {
			hash1[i] = hash1[i-1] * base + s1.charAt(i-1);
			pow[i] = pow[i-1] * base;
		}
		for(int i=1; i<=s2.length(); i++) {
			hash2[i] = hash2[i-1] * base + s2.charAt(i-1);
		}
		int ans = 0;
		for(int i=1; i<=Math.min(s1.length(), s2.length()); i++) {
			long t1 = getSubHash(hash1, pow, s1.length()-i+1, s1.length());
			long t2 = getSubHash(hash2, pow, 1, i);
			if(t1 == t2) ans = i;
//			System.out.println(s1.substring(s1.length()-i, s1.length()) + " " + t1 + "..." +
//					s2.substring(0, i) + " " + t2);
		}
		System.out.println(s1 + s2.substring(ans));
	}
	static long getSubHash(long hash[], long pow[], int l, int r) {
		return hash[r] - hash[l-1] * pow[r-l+1];
	}
	static String next () throws IOException {
		while (st == null || !st.hasMoreTokens())
			st = new StringTokenizer(br.readLine().trim());
		return st.nextToken();
	}
	static long readLong () throws IOException {
		return Long.parseLong(next());
	}
	static int readInt () throws IOException {
		return Integer.parseInt(next());
	}
	static double readDouble () throws IOException {
		return Double.parseDouble(next());
	}
	static char readCharacter () throws IOException {
		return next().charAt(0);
	}
	static String readLine () throws IOException {
		return br.readLine().trim();
	}
}