2021团体程序设计天梯赛 L3-2 还原文件

思路：

dfs+回溯，不加回溯只有26分

Tip：

直接拿纸条往上怼

#include <bits/stdc++.h>

using namespace std;

const int maxn = 100000 + 5;

struct mmp {
    int i;
    int at;
    vector<int> v;
} member[105];

int number[maxn];
int n, p;
bool flag = false;

bool cmp1(mmp a, mmp b) {
    return a.v.size() > b.v.size();
}

bool cmp2(mmp a, mmp b) {
    return a.at < b.at;
}

void dfs(int now) {
    if (now == n && !flag) {
        flag = true;
        sort(member + 1, member + 1 + p, cmp2);
        bool first = true;
        for (int i = 1; i <= p; i++) {
            if (first) {
                first = false;
                cout << member[i].i;
            } else
                cout << " " << member[i].i;
        }
        return;
    }
    for (int i = 1; i <= p; i++) {
        bool flag1 = true;
        for (int j = 0; j < member[i].v.size(); j++) {
            if (member[i].v[j] != number[now + j]) {
                flag1 = false;
                break;
            }
        }
        if (flag1) {
            member[i].at = now;
            dfs(now + member[i].v.size() - 1);
            if (flag)
                return;
        }
    }
}

int main() {
    cin >> n;
    for (int i = 1; i <= n; i++) {
        cin >> number[i];
    }
    cin >> p;
    for (int i = 1; i <= p; i++) {
        int t;
        cin >> t;
        member[i].i = i;
        for (int j = 1; j <= t; j++) {
            int tmp;
            cin >> tmp;
            member[i].v.push_back(tmp);
        }
    }
    sort(member + 1, member + 1 + p, cmp1);
    dfs(1);
    return 0;
}