#include<iostream>
#include<stdio.h>
#include<stdlib.h>
using namespace std;
#define N 10000000
struct BTNode{
    char data;
    BTNode *lchild;
    BTNode *rchild;
}BTNode;
char IN[N],POST[N];
struct BTNode *nil=NULL;
struct BTNode *CreatTree(char IN[],char POST[],int l1,int r1,int l2,int r2)
{
    if(l1>r1)
    {
        return nil;
    }
    struct BTNode *T=(struct BTNode *)malloc(sizeof(BTNode));
    T->lchild=nil; T->rchild=nil;
    T->data=POST[r2];
    int i;
    for(i=l1;i<=r1;i++)
    {
        if(IN[i]==POST[r2])
            break;
    }
    T->lchild=CreatTree(IN, POST, l1, i-1, l2, l2+i-1-l1);
    T->rchild=CreatTree(IN, POST, i+1, r1, l1+i-l2, r1-1);
    return T;
}
int main()
{
    int n;
    scanf("%d",&n);
    for(int i=1;i<=n;i++)
        cin>>IN[i];
    for(int i=1;i<=n;i++)
        cin>>POST[i];
    CreatTree(IN,POST,1,n,1,n);
    
    return 0;
}