#include <bits/stdc++.h>
using namespace std;
const int MAXN = 2000000;
int nxt[MAXN + 5];
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);
    string s, t;
    string ans; //t+#+s
    cin >> s >> t;
    //初始化t+"#", s是占位使用的
    ans = t + "#" + s;
    nxt[0] = 0;
    for (int i = 1; i < t.length() + 1; i++)
    {
        int j = nxt[i - 1];
        while (j > 0 && ans[j] != ans[i])
            j = nxt[j - 1];
        if (ans[j] == ans[i])
            j++;
        nxt[i] = j;
    }
    //把s逐个放进来
    int i = 0;              //把s[i]
    int j = t.length() + 1; //放入ans[j]
    while (i < s.length())
    {
        ans[j] = s[i];
        i++;
        int k = nxt[j - 1];
        while (k > 0 && ans[k] != ans[j])
            k = nxt[k - 1];
        if (ans[k] == ans[j])
            k++;
        nxt[j] = k;
        if (nxt[j] < t.length())
            j++;
        else
            j = j - t.length() + 1;
    }
    for (int i = t.length() + 1; i < j; i++)
        cout << ans[i];
    return 0;
}