Submission #530466

#	Time	Username	Problem	Language	Result	Execution time	Memory
530466		Koosha_mv	Min-max tree (BOI18_minmaxtree)	C++14	0 / 100	68 ms	24832 KiB

minmaxtree

#include <bits/stdc++.h>
using namespace std;
#define dbgv(v) cout<<#v<<" = "; f(i,0,v.size()) cout<<v[i]<<" "; cout<<endl
#define dbga(a,x,y) cout<<#a<<" = "; f(i,x,y) cout<<a[i]<<" "; cout<<endl
#define erorp(x) cout<<#x<<"={"<<(x.F)<<" , "<<x.S<<"}"<<endl
#define eror(x) cout<<#x<<'='<<(x)<<endl
#define f_(i,a,b) for(int i=a;i>=b;i--)
#define f(i,a,b) for(int i=a;i<b;i++)
#define nb(x) __builtin_popcount(x)
#define all(v) v.begin(),v.end()
#define bit(n,k) (((n)>>(k))&1)
#define Add(x,y) x=(x+y)%mod
#define maxm(a,b) a=max(a,b)
#define minm(a,b) a=min(a,b)
#define lst(x) x[x.size()-1]
#define sz(x) int(x.size())
#define mp make_pair
#define ll long long
#define pb push_back
#define S second
#define F first

const int N=1e5+99;

int n,m,rt,a[N],W[N],U[N],V[N],vis[N];
char C[N];
vector<int> vec,g[N],vmn[N],vmx[N];
vector<pair<int,pair<int,int>>> G[N];
set<int> smn[N],smx[N];
map<pair<int,int>,int> mark;

void output(int s,int t,int u,int v){
	int res;
	cout<<s<<" "<<t<<" ";
	if(u==0 || v==0) res=max(u,v);
	else res=v;
	maxm(res,1);
	cout<<vec[res-1];
	cout<<endl;
}
void dfs(int u,int p){
	int x=0;
	for(auto v : g[u]){
		if(v==p) continue ;
		dfs(v,u);
		if(smn[v].size()+smx[v].size()>smn[x].size()+smx[x].size()){
			x=v;
		}
	}
	swap(smn[u],smn[x]);
	swap(smx[u],smx[x]);
	for(auto x : vmn[u]){
		if(smn[u].find(x)!=smn[u].end()) smn[u].erase(x);
		else smn[u].insert(x);
	}
	for(auto x : vmx[u]){
		if(smx[u].find(x)!=smx[u].end()) smx[u].erase(x);
		else smx[u].insert(x);
	}
	for(auto v : g[u]){
		if(v==p || v==x || 1) continue ;
		for(auto x : smn[v]){
			if(smn[u].find(x)!=smn[u].end()) smn[u].erase(x);
			else smn[u].insert(x);
		}
		for(auto x : smx[v]){
			if(smx[u].find(x)!=smx[u].end()) smx[u].erase(x);
			else smx[u].insert(x);
		}
	}
	if(u==1) return ;
	int l=0,r=0;
	if(smn[u].size()) l=*smn[u].rbegin();
	if(smx[u].size()) r=*smx[u].begin();
	//cout<<p<<" "<<u<<" -> "<<l<<" "<<r<<endl;
	G[l].pb({r,{u,p}});
	G[r].pb({l,{u,p}});
}
void dfs1(int u,int p){
	vis[u]=1;
	for(auto v : G[u]){
		if(vis[v.F]){
			if(p!=v.F) rt=v.F;
			continue ;
		}
		dfs1(v.F,u);
	}
}
void dfs2(int u){
	vis[u]=2;
	for(auto p : G[u]){
		int v=p.F,s=p.S.F,t=p.S.S;
		if(!mark[mp(s,t)]){
			//cout<<u<<" "<<v<<endl;
			mark[mp(s,t)]=1;
			output(s,t,u,v);
		}
		if(vis[v]<2){
			dfs2(v);
		}
	}
}
void solve(int u){
	rt=0;
	dfs1(u,u);
	dfs2(rt);
}
int main(){
	ios:: sync_with_stdio(0), cin.tie(0), cout.tie(0);
	cin>>n;
	f(i,1,n){
		int u,v;
		cin>>u>>v;
		g[u].pb(v);
		g[v].pb(u);
	}
	cin>>m;
	f(i,0,m){
		cin>>C[i]>>U[i]>>V[i]>>W[i];
		vec.pb(W[i]);
	}
	sort(all(vec));
	f(i,0,m){
		W[i]=lower_bound(all(vec),W[i])-vec.begin()+1;	
		int u=U[i],v=V[i],w=W[i];
		if(C[i]=='M'){
			vmx[u].pb(w);
			vmx[v].pb(w);
		}
		else{
			vmn[u].pb(w);
			vmn[v].pb(w);
		}
	}
	//dfs(1,1);
	f(i,0,m+1){
		if(!vis[i]){
			solve(i);
		}
	}
}
/*
4 
1 2
2 3
3 4
3
M 1 4 10
m 1 4 0
M 2 3 5
*/

• Subtask 1: 0 / 7
• Subtask 2: 0 / 22
• Subtask 3: 0 / 29
• Subtask 4: 0 / 42