Submission #710104

#	Time	Username	Problem	Language	Result	Execution time	Memory
710104		nicky4321	Jail (JOI22_jail)	C++14	0 / 100	36 ms	74172 KiB

jail

#include <bits/stdc++.h>
#define ll long long
#define ld long double
#define F first
#define S second
#define PB push_back
#define MP make_pair
#define pii pair<int, int>
#define pll pair<ll, ll>
#define pdd pair<double, double>
#define ALL(x) x.begin(), x.end()
#define vi vector<int>
#define vl vector<ll>
#define SZ(x) (int)x.size()
#define CASE int t;cin>>t;for(int ca=1;ca<=t;ca++)
#define IOS ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0);
using namespace std;
const int MAX = 1 << 20, MOD = 1e9 + 7;
vi edge[MAX], p[MAX], e[MAX];
int cnt[MAX], u[MAX], v[MAX], from[MAX], vis[MAX];

bool dfs(int now){
    vis[now] = 1;
    for(int i : e[now]){
        if(vis[i]){
            return 1;
        }
        if(dfs(i))
            return 1;
    }
    return 0;
}

void solve(){
    int n;
    cin >> n;
    for(int i = 1;i <= n;i++){
        p[i].clear();
        edge[i].clear();
        e[i].clear();
    }
    for(int i = 1;i < n;i++){
        int u, v;
        cin >> u >> v;
        edge[u].PB(v);
        edge[v].PB(u);
    }
    int m;
    cin >> m;
    for(int i = 1;i <= m;i++){
        cin >> u[i] >> v[i];
        p[u[i]].PB(i);
        p[v[i]].PB(-i);
    }
    map<pii, int> mp;
    for(int i = 1;i <= m;i++){
        for(int j = 1;j <= n;j++)
            vis[j] = cnt[j] = 0;
        queue<int> q;
        q.push(u[i]);
        while(!q.empty()){
            int now = q.front();
            q.pop();
            for(int i : edge[now]){
                if(!vis[i]){
                    vis[i] = 1;
                    from[i] = now;
                    q.push(i);
                }
            }
        }
        int tmp = v[i];
        while(tmp != u[i]){
            for(int j : p[tmp]){
                if(abs(j) == i)
                    continue;
                if(j < 0 && !mp.count(MP(-j, i))){
                    e[-j].PB(i);
                    mp[MP(-j, i)] = 1;
                }else if(j > 0 && !mp.count(MP(i, j))){
                    e[i].PB(j);
                    mp[MP(i, j)] = 1;
                }
            }
            tmp = from[tmp];
        }
        for(int j : p[tmp]){
            if(abs(j) == i)
                continue;
            if(j < 0 && !mp.count(MP(-j, i))){
                e[-j].PB(i);
                mp[MP(-j, i)] = 1;
            }else if(j > 0 && !mp.count(MP(i, j))){
                e[i].PB(j);
                mp[MP(i, j)] = 1;
            }
        }
    }
    for(int i = 1;i <= m;i++)
        for(int j : e[i])
            cout << i << " " << j << '\n';
    for(int i = 1;i <= m;i++){
        for(int j = 1;j <= m;j++)
            vis[j] = 0;
        if(dfs(i)){
            cout << "No\n";
            return;
        }
    }
    cout << "Yes\n";
}

int main(){
    IOS
    CASE
        solve();
    return 0;
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 5
• Subtask 3: 0 / 16
• Subtask 4: 0 / 28
• Subtask 5: 0 / 12
• Subtask 6: 0 / 11
• Subtask 7: 0 / 23