oj.uz

답안 #17589

# 제출 시각 아이디 문제 언어 결과 실행 시간 메모리
17589 2016-01-01T02:08:50 Z comet 관광지 (IZhO14_shymbulak) C++
100 / 100
 115 ms 22144 KB 
#include<iostream>
#include<vector>
#include<deque>
#include<cstdio>
using namespace std;
typedef long long ll;
typedef pair<int,int> pp;
vector<int> path[222222];
vector<int> cycle;
int n,chk[222222],T,N;
ll Max,cnt,a[222222],b[222222],CNT[422222];
bool isCycle[222222];
deque<ll> index,value;
pp dfs(int v,int p){
	int u,i,z0=0,cnt0=1;
	pp t;
	for(i=0;i<path[v].size();i++){
		u=path[v][i];
		if(u==p||isCycle[u])continue;
		t=dfs(u,v);

		if(z0+t.first+1>Max)Max=z0+t.first+1,cnt=(1ll*cnt0)*t.second;
		else if(z0+t.first+1==Max)cnt+=(1ll*cnt0)*t.second;

		if(z0<t.first)z0=t.first,cnt0=t.second;
		else if(z0==t.first)cnt0+=t.second;
	}
	return pp(z0+1,cnt0);
}
int find_cycle(int v,int p){
	chk[v]=++T;
	int u,i,ret=1e9;
	for(i=0;i<path[v].size();i++){
		u=path[v][i];
		if(u==p)continue;
		if(chk[u]){
			isCycle[v]=1;
			cycle.push_back(v);
			return chk[u];
		}
		ret=min(ret,find_cycle(u,v));
		if(ret<=chk[v]){
			isCycle[v]=1;
			cycle.push_back(v);
			return ret;
		}
	}
	return ret;
}
int main(){
	ios::sync_with_stdio(0);
	cin>>n;
	int x,y;
	for(int i=0;i<n;i++){
		cin>>x>>y;
		path[x].push_back(y);
		path[y].push_back(x);
	}
	find_cycle(1,0);
	pp tt;
	for(int i=0;i<cycle.size();i++){
		tt=dfs(cycle[i],0);
		a[i]=tt.first;
		b[i]=tt.second;
	}
	N=cycle.size()+cycle.size()/2;
	for(int i=cycle.size();i<N;i++)a[i]=a[i-cycle.size()],b[i]=b[i-cycle.size()];
	ll z0,z1,cnt0,cnt1,len=cycle.size()/2,t=0;
	index.push_back(0);
	value.push_back(a[0]);
	CNT[a[0]+N]+=b[0];
	for(int i=1;i<N;i++){
		while((!index.empty())&&index.front()+len<i){
			CNT[value.front()+N]-=b[index.front()];
			index.pop_front();
			value.pop_front();
		}
		if(i>=len){
			z0=value.empty()?0:value.front();
			cnt0=value.empty()?0:CNT[value.front()+N];
			z1=a[i];
			cnt1=b[i];
			if(z0+z1+t>Max)Max=z0+z1+t,cnt=cnt0*cnt1;
			else if(z0+z1+t==Max)cnt+=cnt0*cnt1;
		}
		t++;
		index.push_back(i);
		value.push_back(a[i]-t);
		CNT[a[i]-t+N]+=b[i];
		while(value.size()>1&&value[value.size()-2]<value.back()){
			CNT[value[value.size()-2]+N]-=b[index[index.size()-2]];
			value[value.size()-2]=value.back();
			index[index.size()-2]=index.back();
			value.pop_back();
			index.pop_back();
		}
	}
	cout<<cnt;
}

Subtask #1
30.0 / 30.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 14780 KB Output is correct
2 Correct 0 ms 14780 KB Output is correct
3 Correct 0 ms 14780 KB Output is correct
4 Correct 2 ms 14780 KB Output is correct
5 Correct 2 ms 14780 KB Output is correct
6 Correct 1 ms 14780 KB Output is correct
7 Correct 0 ms 14780 KB Output is correct
8 Correct 0 ms 14780 KB Output is correct
9 Correct 0 ms 14780 KB Output is correct
10 Correct 0 ms 14780 KB Output is correct
11 Correct 0 ms 14780 KB Output is correct
12 Correct 0 ms 14780 KB Output is correct
13 Correct 0 ms 14780 KB Output is correct
14 Correct 3 ms 14912 KB Output is correct
15 Correct 0 ms 14912 KB Output is correct

Subtask #2
20.0 / 20.0

# 결과 실행 시간 메모리 Grader output
1 Correct 0 ms 14912 KB Output is correct
2 Correct 2 ms 14912 KB Output is correct
3 Correct 2 ms 14912 KB Output is correct
4 Correct 0 ms 14912 KB Output is correct
5 Correct 0 ms 15044 KB Output is correct
6 Correct 0 ms 15044 KB Output is correct
7 Correct 5 ms 15044 KB Output is correct
8 Correct 0 ms 15044 KB Output is correct
9 Correct 2 ms 15044 KB Output is correct
10 Correct 0 ms 15044 KB Output is correct

Subtask #3
50.0 / 50.0

# 결과 실행 시간 메모리 Grader output
1 Correct 44 ms 17816 KB Output is correct
2 Correct 46 ms 18212 KB Output is correct
3 Correct 46 ms 21556 KB Output is correct
4 Correct 21 ms 18080 KB Output is correct
5 Correct 39 ms 18080 KB Output is correct
6 Correct 115 ms 20456 KB Output is correct
7 Correct 87 ms 19532 KB Output is correct
8 Correct 69 ms 21248 KB Output is correct
9 Correct 88 ms 21248 KB Output is correct
10 Correct 67 ms 21832 KB Output is correct
11 Correct 85 ms 21748 KB Output is correct
12 Correct 86 ms 22144 KB Output is correct