模拟文件路径

满分代码

/**
模拟文件夹

用什么数据结构存储呢?
1 并查集

难点: 空格的处理
vector<int> vc 存每一层的文件
用p[N] 存上一级
*/
#include <iostream>
#include <cstring>
#include <vector>
using namespace std;
const int N = 1010, M = 10010;;
vector<int> vc[N];
int p[M];

int main()
{
    int m, q, root;
    memset(p, -1, sizeof p);
    cin >> m;
    getchar();
    while (m --)
    {
        string str;
        int cnt = 0;
        getline(cin, str);
        while (str[cnt] == ' ') cnt++;
        int x = stoi(str.substr(cnt));
        vc[cnt].push_back(x);
        if (cnt == 0) p[x] = x, root = x;
        else
        {
            int size = vc[cnt - 1].size();
            p[x] = vc[cnt - 1][size - 1];
        }
    }
    cin >> q;
    while (q --)
    {
        int x;
        cin >> x;
        vector<int> res;
        if (p[x] == -1) printf("Error: %04d is not found.\n", x);
        else
        {
            for(int i = x; i != p[i]; i = p[i]) res.push_back(i);
            res.push_back(root);
            for(int i = res.size() - 1; i >= 0; i--)
            {
                printf("%04d", res[i]);
                if (i) printf("->");
            }
            printf("\n");
        }
    }
}