Submission #890861

#	Time	Username	Problem	Language	Result	Execution time	Memory
890861		vjudge1	Jail (JOI22_jail)	C++17	0 / 100	3 ms	20640 KiB

jail

#include <bits/stdc++.h>
using namespace std;/*
<<<<It's never too late for a new beginning in your life>>>>
Today is hard
  tomorrow will worse
  but the day after tomorrow will be the sunshine..
 
HARD WORK BEATS TALENT WHEN TALENT DOESN'T WORK HARD............
Never give up  */
//The most CHALISHKANCHIK
#define ff first
#define ss second
#define pb push_back
#define all(x) x.begin(),x.end()
#define rall(x) x.rbegin(),x.rend()
#define int long long
typedef vector<int> vi;
typedef pair<int,int> pii;
typedef vector<pair<int,int> > vii;
const long long N = 1e5+50, inf = 1e18, mod = 1e9+7;
vi g[N];
int pre[N];
int timer;
int tin[N], tout[N];
int up[20][N];
void dfs(int v, int pr) {
	//~ cout << pr << ' ' << v << '\n';
	pre[v] = pr;
    tin[v] = ++timer;
    up[0][v] = pr;
    for (int i = 1; i <= 18; i++) {
        up[i][v] = up[i - 1][ up[i - 1][v] ];
    }
    for (int to : g[v]) {
        if (to == pr) continue;
        dfs(to, v);
    }
    tout[v] = timer;
}

bool upper(int a, int b) {
    return tin[a] <= tin[b] && tout[a] >= tout[b];
}

int lca(int a, int b) {
    if (upper(a, b)) return a;
    if (upper(b, a)) return b;
    for (int i = 18; i >= 0; i--) {
        if (!upper(up[i][a], b)) {
            a = up[i][a];
        }
    }
    return up[0][a];
}
vi path(int s, int t){
	int h = lca(s, t);
	vi ans;
	while(s!=h){
		ans.pb(s);
		s = pre[s];
	}
	ans.pb(h);
	vi res;
	while(t!=h){
		res.pb(t);
		t = pre[t];
	}
	reverse(all(res));
	for(auto i:res)ans.pb(i);
	return ans;
}
void solve(){
	int n;
	cin >> n;
	for(int i = 1; i <= n; i++)g[i].clear();
	for(int i = 0; i < n-1; i++){
		int a, b;
		cin >> a >> b;
		g[a].pb(b);
		g[b].pb(a);
	}
	dfs(1, -1);
	int m;
	cin >> m;
	vii ps(m);
	for(int i = 0; i < m; i++){
		cin >> ps[i].ff >> ps[i].ss;
	}
	sort(all(ps));
	int pi, pj;
	for(int i = 0; i < m-1; i++){
		vi pathi = path(ps[i].ff, ps[i].ss);
		pi = pathi.size();
		for(int j = i+1; j < m; j++){
			vi pathj = path(ps[j].ff, ps[j].ss);
			pj = pathj.size();
			for(int k = 0; k < min(pi, pj); k++){
				if(pathi[k] == pathj[k]){
					cout << "No\n";
					return;
				}
			}
		}
	}
	cout << "Yes\n";
}
main(){
	ios_base::sync_with_stdio(false);cin.tie(NULL);cout.tie(NULL);
	int t = 1;
	cin >> t;
	while(t--){
		solve();
	}
}

Compilation message (stderr)

jail.cpp:107:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  107 | main(){
      | ^~~~

• 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