真的降智篇

#include<bits/stdc++.h>
#define pb push_back
#define mp make_pair
#define fi first
#define se second
#define ll long long
#define For(i,a,b) for(int i=a;i<=b;i++)
#define Forr(i,a,b) for(int i=a;i>=b;i--)
#define Fr(i,a,b) for(int i=a;i<b;i++)
#define Frr(i,a,b) for(int i=a;i>b;i--)
using namespace std;
const int maxn=1005;
inline ll read()
{
    ll x=0,f=1;char ch=getchar();
    while(ch<‘0‘||ch>‘9‘){if(ch==‘-‘)f=-1;ch=getchar();}
    while(ch>=‘0‘&&ch<=‘9‘){x=x*10+ch-‘0‘;ch=getchar();}
    return x*f;
}
vector<int>::iterator it;
int a[maxn],b[maxn],L[maxn],R[maxn];
vector<int>vec[maxn];
int n;
int maxx=0;
int build(int l,int r,int zl,int zr)
{
    if(l>r)return 0;
    int rt=a[r];
    int tmp=0;
    for(int i=zl;i<=zr;i++)
    {
        if(b[i]==rt){
            tmp=i;break;
        }
    }
    if(tmp)
    {
        R[rt]=build(r-(zr-tmp),r-1,tmp+1,zr);
        L[rt]=build(l,r-(zr-tmp)-1,zl,tmp-1);
    }
    return rt;
}
void dfs1(int x,int depth)
{
    vec[depth].pb(x);
    maxx=max(maxx,depth);
    if(L[x])dfs1(L[x],depth+1);
    if(R[x])dfs1(R[x],depth+1);
}
int main()
{
    n=read();
    For(i,1,n)
    {
        a[i]=read();
    }
    For(i,1,n) b[i]=read();
    build(1,n,1,n);//cout<<22<<endl;
    dfs1(a[n],0);
    //cout<<222<<endl;
    for(int i=0;i<=maxx;i++)
    {
        for(int j=0;j<vec[i].size();j++)
        {
            if(i==maxx&&j+1==vec[i].size())
            {
                cout<<vec[i][j];
            }
            else cout<<vec[i][j]<<" ";
        }
    }
}