oj.uz

답안 #472623

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
472623 2021-09-13T21:57:06 Z kungfulon Papričice (COCI20_papricice) C++17
110 / 110
 391 ms 29288 KB 
#include <iostream>
#include <vector>
#include <set>
#include <algorithm>
using namespace std;

int n,ans = 1e9;
vector<int> g[200001];
int kids[200001];
multiset<int> si,so;

void DFS(int u,int p = -1){
	kids[u] = 1;
	for(auto v : g[u]) if(v != p){
		DFS(v,u);
		kids[u] += kids[v];
	}
}

inline void calc(int x,int y,int z){
	ans = min(ans,max({abs(x-y),abs(y-z),abs(x-z)}));
}

void solve(int u,int p = -1){
	/// y nam trong x 
	auto in = si.lower_bound((n - kids[u])/2);
	if(in != si.end()){
		calc(*in,n-kids[u]-(*in),kids[u]);
	}
	if(in != si.begin()){
		auto pin = prev(in);
		calc(*pin,n-kids[u]-(*pin),kids[u]);
	}
	/// y nam ngoai x
	auto out = so.lower_bound((n - kids[u])/2);
	if(out != so.end()){
		calc(*out,n-kids[u]-(*out),kids[u]);
	}
	if(out != so.begin()){
		auto pout = prev(out);
		calc(*pout,n-kids[u]-(*pout),kids[u]);
	}

	si.insert(n - kids[u]);
	for(auto v : g[u]) if(v != p){
		solve(v,u);
	}
	so.insert(kids[u]);
	si.erase(si.find(n - kids[u]));
}

int main(int argc,const char** argv){
	cin >> n;
	for(int i = 1;i < n;i++){
		int x,y;
		cin >> x >> y;
		g[x].push_back(y);
		g[y].push_back(x);
	}
	DFS(1);
	solve(1);
	cout << ans;
}

Subtask #1
15.0 / 15.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 4940 KB Output is correct
2 Correct 4 ms 4996 KB Output is correct
3 Correct 3 ms 4940 KB Output is correct
4 Correct 3 ms 4940 KB Output is correct
5 Correct 3 ms 4932 KB Output is correct

Subtask #2
35.0 / 35.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 4940 KB Output is correct
2 Correct 4 ms 4996 KB Output is correct
3 Correct 3 ms 4940 KB Output is correct
4 Correct 3 ms 4940 KB Output is correct
5 Correct 3 ms 4932 KB Output is correct
6 Correct 5 ms 5068 KB Output is correct
7 Correct 5 ms 5068 KB Output is correct
8 Correct 5 ms 5068 KB Output is correct
9 Correct 5 ms 5136 KB Output is correct
10 Correct 5 ms 5068 KB Output is correct

Subtask #3
60.0 / 60.0

# 결과 실행 시간 메모리 Grader output
1 Correct 5 ms 4940 KB Output is correct
2 Correct 4 ms 4996 KB Output is correct
3 Correct 3 ms 4940 KB Output is correct
4 Correct 3 ms 4940 KB Output is correct
5 Correct 3 ms 4932 KB Output is correct
6 Correct 5 ms 5068 KB Output is correct
7 Correct 5 ms 5068 KB Output is correct
8 Correct 5 ms 5068 KB Output is correct
9 Correct 5 ms 5136 KB Output is correct
10 Correct 5 ms 5068 KB Output is correct
11 Correct 346 ms 23956 KB Output is correct
12 Correct 367 ms 23992 KB Output is correct
13 Correct 319 ms 24412 KB Output is correct
14 Correct 342 ms 24184 KB Output is correct
15 Correct 391 ms 24056 KB Output is correct
16 Correct 264 ms 23872 KB Output is correct
17 Correct 341 ms 24112 KB Output is correct
18 Correct 351 ms 29288 KB Output is correct
19 Correct 319 ms 24180 KB Output is correct
20 Correct 341 ms 24064 KB Output is correct