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답안 #574569

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
574569 2022-06-08T20:43:59 Z FatihSolak Min-max tree (BOI18_minmaxtree) C++17
29 / 100
 662 ms 96392 KB 
#include <bits/stdc++.h>
#define N 200005
#define K 20
using namespace std;
vector<int> adj[N];
map<pair<int,int>,pair<int,int>> edge;
int par[N][K];
int dep[N];
set<int> s[N][2];
set<int> del[N][2];
map<int,bool> needed;
void dfs0(int v,int pr){
	par[v][0] = pr;
	dep[v] = dep[pr] + 1;
	for(auto u:adj[v]){
		if(u == pr)continue;
		dfs0(u,v);
	}
}
void dfs1(int v,int pr){
	for(auto u:adj[v]){
		if(u == pr)continue;
		dfs1(u,v);
		for(int i = 0;i<2;i++){
			if(s[u][i].size() > s[v][i].size()){
				swap(s[u][i],s[v][i]);
			}
			for(auto c:s[u][i]){
				s[v][i].insert(c);
			}
		}
	}
	for(int i = 0;i<2;i++){
		for(auto u:del[v][i]){
			s[v][i].erase(u);
		}
	}
	if(s[v][0].size()){
		edge[{min(v,pr),max(v,pr)}].first = max(edge[{min(v,pr),max(v,pr)}].first,*s[v][0].rbegin());
	}
	if(s[v][1].size()){
		edge[{min(v,pr),max(v,pr)}].second = min(edge[{min(v,pr),max(v,pr)}].second,*s[v][1].begin());
	}
}
int lca(int u,int v){
	if(dep[u] < dep[v])swap(u,v);
	for(int j = K-1;j>=0;j--){
		if(dep[par[u][j]] >= dep[v]){
			u = par[u][j];
		}
	}
	if(u == v)
		return u;
	for(int j = K-1;j>=0;j--){
		if(par[u][j] != par[v][j]){
			u = par[u][j];
			v = par[v][j];
		}
	}
	return par[u][0];
}
void solve(){
	int n;
	cin >> n;
	map<pair<int,int>,int> ans;
	for(int i = 1;i<n;i++){
		int u,v;
		cin >> u >> v;
		adj[u].push_back(v);
		adj[v].push_back(u);
		edge[{min(u,v),max(u,v)}] = {-2e9,2e9};
		ans[{min(u,v),max(u,v)}] = 0;
	}
	dfs0(1,0);
	for(int j = 1;j<K;j++){
		for(int i = 1;i<=n;i++){
			par[i][j] = par[par[i][j-1]][j-1];
		}
	}
	int k;
	cin >> k;
	for(int i = 1;i<=k;i++){
		char type;
		int u,v,x;
		cin >> type >> u >> v >> x;
		needed[x] = 1;
		int lc = lca(u,v);
		if(type == 'M'){
			s[u][1].insert(x);
			s[v][1].insert(x);
			del[lc][1].insert(x);
		}
		if(type == 'm'){
			s[u][0].insert(x);
			s[v][0].insert(x);
			del[lc][0].insert(x);
		}
	}
	dfs1(1,0);
	map<int,set<pair<int,pair<int,int>>>> adj2;
	for(auto u:edge){
		if(needed[u.second.first]){
			adj2[u.second.first].insert({u.second.second,u.first});
		}
		if(needed[u.second.second]){
			adj2[u.second.second].insert({u.second.first,u.first});
		}
	}
	set<pair<int,int>> ss;
	for(auto u:adj2){
		ss.insert({u.second.size(),u.first});
	}
	while(ss.size()){
		int num = ss.begin()->second;
		ss.erase(ss.begin());
		needed[num] = 0;
		ans[adj2[num].begin()->second] = num;
		if(needed[adj2[num].begin()->first]){
			ss.erase({adj2[adj2[num].begin()->first].size(),adj2[num].begin()->first});
			adj2[adj2[num].begin()->first].erase({num,adj2[num].begin()->second});
			ss.insert({adj2[adj2[num].begin()->first].size(),adj2[num].begin()->first});
		}

	}
	assert(ans.size() == n-1);
	for(auto u:ans){
		cout << u.first.first << " " << u.first.second << " "<< u.second << endl;
	}
}
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(nullptr);
	#ifdef Local
		freopen("in.txt","r",stdin);
		freopen("out.txt","w",stdout);
	#endif
	int t = 1;
	//cin >> t;
	while(t--){
		solve();
	}
	#ifdef Local
		cout << endl << fixed << setprecision(2) << 1000.0 * clock() / CLOCKS_PER_SEC << " milliseconds.";
	#endif
}

Compilation message

In file included from /usr/include/c++/10/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/10/bits/stdc++.h:33,
                 from minmaxtree.cpp:1:
minmaxtree.cpp: In function 'void solve()':
minmaxtree.cpp:125:20: warning: comparison of integer expressions of different signedness: 'std::map<std::pair<int, int>, int>::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
  125 |  assert(ans.size() == n-1);
      |         ~~~~~~~~~~~^~~~~~

Subtask #1
7.0 / 7.0

# 결과 실행 시간 메모리 Grader output
1 Correct 20 ms 42580 KB Output is correct
2 Correct 21 ms 42520 KB Output is correct
3 Correct 23 ms 42532 KB Output is correct
4 Correct 19 ms 42580 KB Output is correct

Subtask #2
22.0 / 22.0

# 결과 실행 시간 메모리 Grader output
1 Correct 662 ms 95044 KB Output is correct
2 Correct 649 ms 92008 KB Output is correct
3 Correct 617 ms 88244 KB Output is correct
4 Correct 653 ms 96392 KB Output is correct
5 Correct 642 ms 90068 KB Output is correct
6 Correct 592 ms 89196 KB Output is correct
7 Correct 571 ms 84176 KB Output is correct

Subtask #3
0 / 29.0

# 결과 실행 시간 메모리 Grader output
1 Incorrect 353 ms 70636 KB Output isn't correct
2 Halted 0 ms 0 KB -

Subtask #4
0 / 42.0

# 결과 실행 시간 메모리 Grader output
1 Correct 20 ms 42580 KB Output is correct
2 Correct 21 ms 42520 KB Output is correct
3 Correct 23 ms 42532 KB Output is correct
4 Correct 19 ms 42580 KB Output is correct
5 Correct 662 ms 95044 KB Output is correct
6 Correct 649 ms 92008 KB Output is correct
7 Correct 617 ms 88244 KB Output is correct
8 Correct 653 ms 96392 KB Output is correct
9 Correct 642 ms 90068 KB Output is correct
10 Correct 592 ms 89196 KB Output is correct
11 Correct 571 ms 84176 KB Output is correct
12 Incorrect 353 ms 70636 KB Output isn't correct
13 Halted 0 ms 0 KB -