北航计算机夏令营机试（？）三叉树

题目详情请参见：https://blog.csdn.net/weixin_43347688/article/details/114538022

代码：

#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int MOD = 1e9+7;
 
int n, m; int a[110], b[110];
map<int, vector<int>> mp;
int x,y,z,w; int goal[1000];
 
int main(){
    ios::sync_with_stdio(false);
    cin>>n;
    for(int i=0; i<n; ++i){
        cin>>x>>y>>z>>w;
        if(i==0){
            goal[0] = x; mp[x]=vector<int>();
            mp[x].push_back(-1), mp[x].push_back(x);
        }
        if(y!=-1) mp[y]=vector<int>(mp[x]), mp[y].push_back(y);
        if(z!=-1) mp[z]=vector<int>(mp[x]), mp[z].push_back(z);
        if(w!=-1) mp[w]=vector<int>(mp[x]), mp[w].push_back(w);
    }
    cin>>m;
    for(int i=0; i<m; ++i){
        cin>>x>>y; goal[y+1]=x;
    }
    goal[m+1] = goal[0];
    for(int i=1; i<=m+1; ++i){
        vector<int> path1 = mp[goal[i-1]];
        vector<int> path2 = mp[goal[i]];
        int j;
        for(j=0; j<path1.size() && j<path2.size(); ++j){
            if(path1[j]!=path2[j]) break;
        }
        --j;
        if(i==1)
            for(int k=path1.size()-1; k>j; --k) cout<<path1[k]<<" ";
        else
            for(int k=path1.size()-2; k>j; --k) cout<<path1[k]<<" ";
        for(int k=j; k<path2.size(); ++k) cout<<path2[k]<<" ";
        cout<<endl;
    }
}
 
 
/*
 
10
100 101 108 107
101 1 102 2
108 103 104 105
107 17 109 18
102 3 4 5
103 7 8 9
104 10 106 11
105 15 16 -1
109 19 20 21
106 12 13 14
5
8 1
14 3
16 2
5 0
19 4
 
*/