//知道中序后序求先序
#include<iostream>#include<cstdio>#include<cstring>#include<string>using namespace std;const int N=10;int la,lb;char a[N],b[N];struct node{    int ls,rs;    char c;}tree[N];int cnt=0;int build(int l,int r,int s,int t){    if(l>r||s>t) return 0;    tree[++cnt].c=b[t]; int u=cnt;    int root=0;    for(root=l;root<=r;root++) if(a[root]==b[t]) break;    tree[u].ls=build(l,root-1,s,s+root-l-1);    tree[u].rs=build(root+1,r,s+root-l,t-1);     return u;}void print(int u){    if(u==0) return;    printf("%c",tree[u].c);    print(tree[u].ls);    print(tree[u].rs);}int main(){    scanf("%s%s",a+1,b+1);    la=strlen(a+1);lb=strlen(b+1);    build(1,la,1,lb);      print(1);  }