oj.uz

답안 #604104

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
604104 2022-07-24T18:14:03 Z l_reho Stranded Far From Home (BOI22_island) C++14
35 / 100
 396 ms 31000 KB 
#include<bits/stdc++.h>
using namespace std;

#define ll long long

struct info{
	int node;
	ll people;
	
	bool operator <(const info &i) const{
		return people > i.people;
	}
	
};

int N, M;

vector<ll> A;
vector<pair<ll, int>> A1;
vector<bool> taken, vis;
vector<vector<int>> graph;
vector<ll> P;

void dfs(int curr){
	vis[curr] = true;
	
	vector<int> adj = graph[curr];
	
	P[curr] = A[curr];
	
	for(int a : adj){
		if(vis[a]) continue;
		dfs(a);
		
		P[curr] += P[a];
		
	}
	
	
	// cout<<curr<<" "<<P[curr]<<endl;
}
/*

5 4
40 15 50 31 31
1 2
2 3
3 4
4 5
 
 
*/
void solver(int curr, int p, vector<int> &ans){
	vis[curr] = true;
	vector<int> adj = graph[curr];
	
	if((int)adj.size() == 1 && curr){
		if(P[curr] >= A[p]){
			ans[curr] = 1;
		}else{
			ans[curr] = 0;
		}
		return;
	}
	
	for(int a : adj){
		if(vis[a]) continue;
		
		if(curr){
			if(P[curr] >= A[p]){
				ans[curr] = 1;
			}else{
				ans[curr] = 0;
				continue;
			}
		}
		
		solver(a, curr, ans);
		
	}
	
}

void solve(){
	cin>>N>>M;
	
	A.assign(N, 0);
	A1.assign(N, pair<ll, int>());
	
	P.assign(N, 0);
	
	graph.assign(N, vector<int>());
	vis.assign(N, false);
	
	for(int i = 0; i < N; i++){
		int v;
		cin>>v;
		A[i] = v;
		A1[i] = {v, i};
	}
	
	sort(A1.begin(), A1.end(), greater<pair<ll, int>>());
	
	bool subtask3 = true;
	
	for(int i = 0; i < M; i++){
		int a, b;
		cin>>a>>b;
		a--;
		b--;
		graph[a].push_back(b);
		graph[b].push_back(a);
		
		subtask3 &= abs(a-b) == 1;
	}
	vector<int> ans(N, 2);
	
	
	ll sum = accumulate(A.begin(), A.end(), 0LL);
	
	bool subtask1 = (N <= 2000 && M <= 2000);
	
	if(subtask1){
		int last_color = N;
		
		for(int color = 0; color < last_color; color++){
			if(ans[color] != 2) continue;
			priority_queue<info> pq;
			// inizializzo la pq
			vector<int> adj = graph[color];
			
			taken.assign(N, false);
			taken[color] = true;
			
			for(int a : adj)
				pq.push({a, A[a]});
			
			ll total = A[color];
			stack<int> nodes;
			
			while(!pq.empty()){
				info i = pq.top();
				
				pq.pop();
				
				int node = i.node;
				ll abitants = i.people;
				
				if(taken[node]) continue;
				
				taken[node] = true;
				
				if(abitants > total)
					break;
				
				if(ans[node] == 1){
					total = sum;
					break;
				}
					
				nodes.push(node);
				total += abitants;
				vector<int> adj = graph[node];

				for(int a : adj){
					if(taken[a]) continue;
					pq.push({a, A[a]});
				}
				
			}
			// se ans[color] è false, allora saranno false anche tutti quelli
			// che sono stati convinti durante il processo e quindi è inutile
			// ricalcolarli
			ans[color] = total == sum;
			if(!ans[color]){
				while(!nodes.empty()){
					ans[nodes.top()] = 0;
					nodes.pop();
				}
			}
		}
		
		for(int i = 0; i < N; i++) cout<<ans[i];
		cout<<endl;
		return;
	}

	if(subtask3){
		vector<ll> pref_sum(N+1, 0);
		
		for(int i = 0; i < N; i++){
			pref_sum[i+1] += pref_sum[i] + A[i];
		}
		
		set<int> s;
		ans[A1[0].second] = 1;
		s.insert(A1[0].second);
		for(int i = 1; i < N; i++){
			int color = A1[i].second;
			// mi serve il primo abitante sulla sinistra già preso e 
			// il primo abitante sulla destra già preso cioè ans[i] = true;
			auto r = s.lower_bound(color);
			auto l = r;
			int r_idx = 0;
			int l_idx = 0;
			
			if(l == s.begin()){
				l_idx = -1;
			}else l_idx = *(--l);
			
			
			if(r == s.end()){
				r_idx = N;
			}else r_idx = *r;
			
			// cout<<"DEBUG-->"<<color<<" "<<l_idx<<" "<<r_idx<<endl;
			if(l_idx == -1)
				ans[color] = (pref_sum[r_idx] - pref_sum[l_idx+1]) >= A[r_idx];
			else if(r_idx == N)
				ans[color] = (pref_sum[r_idx] - pref_sum[l_idx+1]) >= A[l_idx];
			else ans[color] = (pref_sum[r_idx] - pref_sum[l_idx+1]) >= min(A[r_idx], A[l_idx]);
			
			if(ans[color])
				s.insert(color);
		}
		
		for(int i = 0; i < N; i++) cout<<ans[i];
		cout<<endl;
		return;
	}

	dfs(0);

	vis.assign(N, false);
	ans.assign(N, false);
	
	ans[0] = 1;
	
	solver(0, -1, ans);
	
	for(int i = 0; i < N; i++) cout<<ans[i];
	cout<<endl;
	
}

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

Subtask #1
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 4 ms 468 KB Output is correct
5 Correct 4 ms 468 KB Output is correct
6 Correct 4 ms 340 KB Output is correct
7 Correct 6 ms 432 KB Output is correct
8 Correct 4 ms 340 KB Output is correct
9 Correct 3 ms 468 KB Output is correct
10 Correct 4 ms 468 KB Output is correct
11 Correct 3 ms 468 KB Output is correct
12 Correct 4 ms 468 KB Output is correct
13 Correct 2 ms 468 KB Output is correct
14 Correct 9 ms 468 KB Output is correct

Subtask #2
10.0 / 10.0

# 결과 실행 시간 메모리 Grader output
1 Correct 1 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 315 ms 31000 KB Output is correct
4 Correct 262 ms 28432 KB Output is correct
5 Correct 321 ms 18144 KB Output is correct
6 Correct 341 ms 18636 KB Output is correct
7 Correct 337 ms 18628 KB Output is correct
8 Correct 337 ms 18632 KB Output is correct
9 Correct 288 ms 18520 KB Output is correct
10 Correct 257 ms 19984 KB Output is correct
11 Correct 255 ms 20144 KB Output is correct
12 Correct 273 ms 18712 KB Output is correct
13 Correct 208 ms 19968 KB Output is correct
14 Correct 244 ms 21024 KB Output is correct
15 Correct 315 ms 29456 KB Output is correct
16 Correct 286 ms 29208 KB Output is correct

Subtask #3
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 360 ms 24932 KB Output is correct
3 Correct 367 ms 25112 KB Output is correct
4 Correct 324 ms 29432 KB Output is correct
5 Correct 224 ms 19996 KB Output is correct
6 Correct 311 ms 25096 KB Output is correct
7 Correct 331 ms 29464 KB Output is correct
8 Correct 307 ms 29448 KB Output is correct
9 Correct 251 ms 29132 KB Output is correct
10 Correct 272 ms 24728 KB Output is correct
11 Correct 213 ms 20260 KB Output is correct

Subtask #4
0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Incorrect 396 ms 20776 KB Output isn't correct
3 Halted 0 ms 0 KB -

Subtask #5
0 / 35.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 212 KB Output is correct
2 Correct 1 ms 212 KB Output is correct
3 Correct 1 ms 212 KB Output is correct
4 Correct 4 ms 468 KB Output is correct
5 Correct 4 ms 468 KB Output is correct
6 Correct 4 ms 340 KB Output is correct
7 Correct 6 ms 432 KB Output is correct
8 Correct 4 ms 340 KB Output is correct
9 Correct 3 ms 468 KB Output is correct
10 Correct 4 ms 468 KB Output is correct
11 Correct 3 ms 468 KB Output is correct
12 Correct 4 ms 468 KB Output is correct
13 Correct 2 ms 468 KB Output is correct
14 Correct 9 ms 468 KB Output is correct
15 Correct 1 ms 212 KB Output is correct
16 Correct 1 ms 212 KB Output is correct
17 Correct 315 ms 31000 KB Output is correct
18 Correct 262 ms 28432 KB Output is correct
19 Correct 321 ms 18144 KB Output is correct
20 Correct 341 ms 18636 KB Output is correct
21 Correct 337 ms 18628 KB Output is correct
22 Correct 337 ms 18632 KB Output is correct
23 Correct 288 ms 18520 KB Output is correct
24 Correct 257 ms 19984 KB Output is correct
25 Correct 255 ms 20144 KB Output is correct
26 Correct 273 ms 18712 KB Output is correct
27 Correct 208 ms 19968 KB Output is correct
28 Correct 244 ms 21024 KB Output is correct
29 Correct 315 ms 29456 KB Output is correct
30 Correct 286 ms 29208 KB Output is correct
31 Correct 0 ms 212 KB Output is correct
32 Correct 360 ms 24932 KB Output is correct
33 Correct 367 ms 25112 KB Output is correct
34 Correct 324 ms 29432 KB Output is correct
35 Correct 224 ms 19996 KB Output is correct
36 Correct 311 ms 25096 KB Output is correct
37 Correct 331 ms 29464 KB Output is correct
38 Correct 307 ms 29448 KB Output is correct
39 Correct 251 ms 29132 KB Output is correct
40 Correct 272 ms 24728 KB Output is correct
41 Correct 213 ms 20260 KB Output is correct
42 Correct 0 ms 212 KB Output is correct
43 Incorrect 396 ms 20776 KB Output isn't correct
44 Halted 0 ms 0 KB -