#include <iostream>
using namespace std;
void build(int n,char* s1,char *s2,char *s)
{
    if (n <= 0)return;
    int p = strchr(s2, s1[0]) - s2;//找到根结点在中序遍历中的位置
    build(p, s1 + 1, s2, s);//递归构造左子树的后序遍历
    build(n - p - 1, s1 + p + 1, s2 + p + 1, s + p);//递归构造右子数的后序遍历
    s[n - 1] = s1[0];
}
int main()
{
    char s1[1000], s2[1000];
    while (scanf("%s%s", s1, s2) == 2)
    {
        int n = strlen(s1);
        char s[1000];
        build(n, s1, s2, s);
        s[n] = ‘\0‘;
        printf("%s\n", s);
    }
}