#pragma comment(linker, "/STACK:102400000, 102400000")

#include<cstdio>

#include<cstring>

#include<cstdlib>

#include<cctype>

#include<cmath>

#include<iostream>

#include<sstream>

#include<iterator>

#include<algorithm>

#include<string>

#include<vector>

#include<set>

#include<map>

#include<stack>

#include<deque>

#include<queue>

#include<list>

#define Min(a, b) ((a < b) ? a : b)

#define Max(a, b) ((a < b) ? b : a)

typedef long long ll;

typedef unsigned long long llu;

const int INT_INF = 0x3f3f3f3f;

const int INT_M_INF = 0x7f7f7f7f;

const ll LL_INF = 0x3f3f3f3f3f3f3f3f;

const ll LL_M_INF = 0x7f7f7f7f7f7f7f7f;

const int dr[] = {, , -, , -, -, , };

const int dc[] = {-, , , , -, , -, };

const int MOD = 1e9 + ;

const double pi = acos(-1.0);

const double eps = 1e-;

const int MAXN =  + ;

const int MAXT =  + ;

using namespace std;

char pre_order[MAXN];

char in_order[MAXN];

int leftchild[MAXN];

int rightchild[MAXN];

int build(int L1, int R1, int L2, int R2){

    if(L1 > R1) return ;

    int root = pre_order[L1] - 'A' + ;

    int st = L2;

    while((in_order[st] - 'A' + ) != root) ++st;

    int cnt = st - L2;

    leftchild[root] = build(L1 + , L1 + cnt, L2, L2 + cnt - );

    rightchild[root] = build(L1 +  + cnt, R1, st + , R2);

    return root;

}

void dfs(int root){

    if(leftchild[root]) dfs(leftchild[root]);

    if(rightchild[root]) dfs(rightchild[root]);

    printf("%c", root + 'A' - );

}

int main(){

    while(scanf("%s", pre_order) != EOF){

        scanf("%s", in_order);

        int len = strlen(pre_order);

        build(, len - , , len - );

        int root = pre_order[] - 'A' + ;

        dfs(root);

        printf("\n");

    }

    return ;

}