POJ2255

#include<iostream>
#include<cstdio>
#include<string.h>
using namespace std;
void postorder(char *prestart,char *preend,char *instart,char *inend)
{
     char root=*prestart;
     int len=preend-prestart;
     int i;
     for(i=0;*(instart+i)!=root&&i<=len;i++);
     if(i!=0)postorder(prestart+1,prestart+i,instart,instart+i-1);
     if(i!=len)postorder(prestart+i+1,preend,instart+i+1,inend);
     if(root!=0)printf("%c",root);
}
int main()
{
    char preorder[27],inorder[27];
    while(scanf("%s",preorder)!=EOF)
    {
          scanf("%s",inorder);
          int len=strlen(preorder);
          postorder(preorder,preorder+len,inorder,inorder+len);
          printf("\n");
    }
    return 0;
}