oj.uz

Submission #316173

# Submission time Handle Problem Language Result Execution time Memory
316173 2020-10-25T16:26:35 Z kshitij_sodani Papričice (COCI20_papricice) C++14
110 / 110
 462 ms 42744 KB 
#include <bits/stdc++.h>
using namespace std;
typedef long long llo;
#define mp make_pair
#define pb push_back
#define a first 
#define b second
#define endl '\n' 


llo n;
vector<llo> adj[200001];
set<llo> cur;
llo ss[200001];
llo ans;


void dfs(llo no,llo par=-1){
	ss[no]=1;
	for(auto j:adj[no]){
		if(j!=par){
			dfs(j,no);
			ss[no]+=ss[j];
		}
	}
}
set<llo> pre[200001];
void re(llo aa,llo bb,llo cc){
	ans=min(ans,max(max(abs(aa-bb),abs(bb-cc)),abs(aa-cc)));
}
llo dfs2(llo no,llo par=-1){
	if(no!=0){
		auto j=cur.lower_bound((n-ss[no]+1)/2);
		
		if(j!=cur.end()){
			re(*j,ss[no],n-*j-ss[no]);
		}
		if(j!=cur.begin()){
			j--;
			re(*j,ss[no],n-*j-ss[no]);
		}
	}
	llo ma=0;
	llo ind=-1;
	vector<llo> pp;
	for(auto j:adj[no]){
		if(j!=par){
			llo x=dfs2(j,no);
			if(pre[x].size()>ma){
				ma=pre[x].size();
				ind=x;
			}
			pp.pb(x);
		}
	}
	for(auto j:pp){
		if(j!=ind){
			for(auto jj:pre[j]){
				pre[ind].insert(jj);
			}
		}
	}

	



	

	




	cur.insert(ss[no]);
	if(ind==-1){
		pre[no].insert(ss[no]);
		return no;
	}
	if(no!=0){
		auto j=pre[ind].lower_bound((ss[no]+1)/2);
		if(j!=pre[ind].end()){
			re(*j,ss[no]-*j,n-ss[no]);
		}
		if(j!=pre[ind].begin()){
			j--;
			re(*j,ss[no]-*j,n-ss[no]);
		}
	}

	pre[ind].insert(ss[no]);
	return ind;
	
}
int main(){
	ios_base::sync_with_stdio(false);
	cin.tie(NULL);
	cin>>n;
	ans=n;
	for(llo i=0;i<n-1;i++){
		llo aa,bb;
		cin>>aa>>bb;
		aa--;
		bb--;
		adj[aa].pb(bb);
		adj[bb].pb(aa);
	}
	dfs(0);
	dfs2(0);

	cout<<ans<<endl;


	return 0;
}

Compilation message

papricice.cpp: In function 'llo dfs2(llo, llo)':
papricice.cpp:50:20: warning: comparison of integer expressions of different signedness: 'std::set<long long int>::size_type' {aka 'long unsigned int'} and 'llo' {aka 'long long int'} [-Wsign-compare]
   50 |    if(pre[x].size()>ma){
      |       ~~~~~~~~~~~~~^~~

Subtask #1
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 14464 KB Output is correct
2 Correct 10 ms 14464 KB Output is correct
3 Correct 10 ms 14464 KB Output is correct
4 Correct 11 ms 14464 KB Output is correct
5 Correct 10 ms 14464 KB Output is correct

Subtask #2
35.0 / 35.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 14464 KB Output is correct
2 Correct 10 ms 14464 KB Output is correct
3 Correct 10 ms 14464 KB Output is correct
4 Correct 11 ms 14464 KB Output is correct
5 Correct 10 ms 14464 KB Output is correct
6 Correct 13 ms 14592 KB Output is correct
7 Correct 12 ms 14592 KB Output is correct
8 Correct 11 ms 14592 KB Output is correct
9 Correct 11 ms 14592 KB Output is correct
10 Correct 12 ms 14592 KB Output is correct

Subtask #3
60.0 / 60.0

# Verdict Execution time Memory Grader output
1 Correct 11 ms 14464 KB Output is correct
2 Correct 10 ms 14464 KB Output is correct
3 Correct 10 ms 14464 KB Output is correct
4 Correct 11 ms 14464 KB Output is correct
5 Correct 10 ms 14464 KB Output is correct
6 Correct 13 ms 14592 KB Output is correct
7 Correct 12 ms 14592 KB Output is correct
8 Correct 11 ms 14592 KB Output is correct
9 Correct 11 ms 14592 KB Output is correct
10 Correct 12 ms 14592 KB Output is correct
11 Correct 303 ms 34308 KB Output is correct
12 Correct 358 ms 35192 KB Output is correct
13 Correct 288 ms 34540 KB Output is correct
14 Correct 345 ms 34628 KB Output is correct
15 Correct 337 ms 35096 KB Output is correct
16 Correct 223 ms 33636 KB Output is correct
17 Correct 462 ms 34356 KB Output is correct
18 Correct 288 ms 42744 KB Output is correct
19 Correct 337 ms 35704 KB Output is correct
20 Correct 306 ms 35448 KB Output is correct