Submission #622972

#	Time	Username	Problem	Language	Result	Execution time	Memory
622972		inksamurai	Mag (COCI16_mag)	C++17	24 / 120	621 ms	262148 KiB

mag

#include <bits/stdc++.h>
#define int ll
using namespace std;
#define rep(i,n) for(int i=0;i<n;i++)
#define per(i,n) for(int i=n-1;i>=0;i--)
#define fi first
#define se second
#define pb push_back
#define sz(a) (int)a.size()
#define vec(...) vector<__VA_ARGS__>
#define _3SgiE60 ios::sync_with_stdio(0),cin.tie(0)
typedef long long ll;
using pii=pair<int,int>;
using vi=vector<int>;
void print(){cout<<'\n';}
template<class h,class...t>
void print(const h&v,const t&...u){cout<<v<<' ',print(u...);}
// e

const int inf=1e12;

pii compare(const pii&l,const pii&r){
	return l.fi*r.se<r.fi*l.se?l:r;
}

signed main(){
_3SgiE60;
	int n;
	cin>>n;
	vec(vi) adj(n);
	rep(i,n-1){
		int u,v;
		cin>>u>>v;
		u-=1,v-=1;
		adj[u].pb(v);
		adj[v].pb(u);	
	}
	vi a(n);
	rep(i,n){
		cin>>a[i];
	}
	vec(vec(pii)) rbts(n);
	vi ctr(n);
	// center of rabbits
	rep(v,n){
		ctr[v]=v;
	}
	vi dist(n);
	vec(pii) fdp(n);
	auto pre_dfs=[&](auto self,int v,int par)->void{
		int now_ctr=v;
		// print(v,dist[v]);
		for(auto &u:adj[v]){
			if(u==par) continue;
			dist[u]=dist[v]+1;
			self(self,u,v);
			if(sz(rbts[ctr[u]])>sz(rbts[now_ctr])){
				now_ctr=ctr[u];
			}
		}
		for(auto &u:adj[v]){
			if(u==par or ctr[u]==now_ctr) continue;
			for(auto &p:rbts[ctr[u]]){
				rbts[now_ctr].pb(p);
			}
		}
		ctr[v]=now_ctr;
		if(a[v]>1){
			sort(rbts[now_ctr].begin(), rbts[now_ctr].end());
			while(sz(rbts[now_ctr]) and rbts[now_ctr].back().fi>inf/a[v]){
				rbts[now_ctr].pop_back();
			}
			fdp[v]=pii(a[v],1);
			for(auto &p:rbts[now_ctr]){
				p.fi*=a[v];
				fdp[v]=compare(fdp[v],pii(p.fi,dist[p.se]-dist[v]+1));
			}
		}else{
			fdp[v]=pii(1,1);
			for(auto &u:adj[v]){
				if(u==par) continue;
				fdp[v]=compare(fdp[v],pii(fdp[u].fi,fdp[u].se+1));
			}
		}
		rbts[now_ctr].pb(pii(a[v],v));
	};
	pre_dfs(pre_dfs,0,-1);
	pii pns={inf,1};
	auto dfs=[&](auto self,int v,int par)->void{
		pii q={inf,1};
		// print(v);
		for(auto &u:adj[v]){
			if(u==par) continue;
			self(self,u,v);
			pii p=fdp[u];
			if(q.fi<=inf and q.fi<=inf/a[v]/p.fi+1){
				pii now={q.fi*p.fi*a[v],q.se+p.se+1};
				pns=compare(pns,now);
			}
			{
				pii now={p.fi*a[v],p.se+1};
				pns=compare(pns,now);
			}
			q=compare(q,p);
		}
		pns=compare(pns,fdp[v]);
	};
	dfs(dfs,0,-1);
	int g=gcd(pns.fi,pns.se);
	pns.fi/=g;
	pns.se/=g;
	cout<<pns.fi<<"/"<<pns.se<<"\n";
}

• Subtask 1: 0 / 12
• Subtask 2: 12 / 12
• Subtask 3: 0 / 12
• Subtask 4: 0 / 12
• Subtask 5: 0 / 12
• Subtask 6: 0 / 12
• Subtask 7: 0 / 12
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• Subtask 9: 0 / 12
• Subtask 10: 12 / 12