HDOJ 1710

#include <iostream>#include <cstdio>#include <cstring>using namespace std;void build(int n,int *s1,int *s2,int *s){    if(n<=0)        return;    int p;    for(int i=0; i<n; i++)    {        if(s1[0]==s2[i])        {            p=i;        }    }    build(p,s1+1,s2,s);    build(n-p-1,s1+p+1,s2+p+1,s+p);    s[n-1]=s1[0];}const int MAXN=1001;int s1[MAXN],s2[MAXN],ans[MAXN];int main(){    int n;      while(cin>>n)      {          for(int i=0; i<n; i++)        {            cin>>s1[i];        }        for(int i=0; i<n; i++)        {            cin>>s2[i];        }        build(n,s1,s2,ans);        for(int i=0; i<n; i++)        {            printf("%d",ans[i]);            if(i<n-1)                printf(" ");        }        cout<<endl;      }    return 0;}

二叉树知道先序遍历和中序遍历求后序遍历。。。可惜PE了一次，坑爹啊