제출 #889609

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
889609		vjudge1	Tourism (JOI23_tourism)	C++17	28 / 100	5086 ms	16496 KiB

tourism

#include <bits/stdc++.h>
using namespace std;

#define ff first
#define ss second
#define all(a) a.begin(), a.end()
const int mod = 998244353;
const int N = 1e5;

vector<int> g[N+1];
int depth[N+1], c[N+1];
int timer=1;
int tin[N+1], tout[N+1];
int up[N+1][18];
int n, m, q;

void dfs(int v, int par){
	up[v][0] = par;
	tin[v] = timer++;
	for(int i = 1;i < 18; i++){
		up[v][i] = up[up[v][i-1]][i-1];
	}
	for(int to : g[v]){
		if(to == par) continue;
		depth[to] = depth[v] + 1;
		dfs(to, v);
	}
	tout[v] = timer++;
}

int lca(int a, int b){
	if(depth[a] > depth[b]) swap(a, b);
	int k = depth[b] - depth[a];
	for(int i = 0;i < 18; i++){
		if(k & (1<<i)){
			b = up[b][i];
		}
	}
	if(a == b) return a;
	for(int i = 17; i >= 0; i--){
		if(up[a][i] != up[b][i]){
			a = up[a][i];
			b = up[b][i];
		}
	}
	return up[a][0];
}

int vert;
vector<int> vec;


int in_subtree(int v){
	int it = lower_bound(all(vec), tin[v]) - vec.begin();
	if(it < (int)vec.size() && vec[it] <= tout[v]) return 1;
	return 0;
}

void ans(int v, int par){
	if(!in_subtree(v)) return;
	vert++;
	for(int to : g[v]){
		if(to == par) continue;
		ans(to, v);
	}
}

signed main(){
	ios::sync_with_stdio(0);
	cin.tie(0); cout.tie(0);
	 cin >> n >> m >> q;
	for(int i = 1;i < n; i++){
		int a, b; cin >> a >> b;
		g[a].push_back(b);
		g[b].push_back(a);
	}
	for(int i = 0;i < m; i++){
		cin >> c[i];
	}
	dfs(1, 1);
	while(q--){
		int l, r; cin >> l >> r;
		l--, r--;
		int mn = c[l], mx = c[l];
		vec.clear();
		for(int i = l;i <= r; i++){
			vec.push_back(tin[c[i]]);
			if(tin[mn] > tin[c[i]]){
				mn = c[i];
			}
			if(tin[mx] < tin[c[i]]){
				mx = c[i];
			}
		}
		sort(all(vec));
		vec.erase(unique(all(vec)), vec.end());
		vert = 0;
		int lc = lca(mn, mx);
		ans(lc, up[lc][0]);
		
		cout << vert << '\n';
		
	}
	
	return 0;
}

• Subtask 1: 5 / 5
• Subtask 2: 5 / 5
• Subtask 3: 0 / 7
• Subtask 4: 18 / 18
• Subtask 5: 0 / 24
• Subtask 6: 0 / 41