Submission #863606

#	Time	Username	Problem	Language	Result	Execution time	Memory
863606		Huseyn123	Dreaming (IOI13_dreaming)	C++17	77 / 100	1092 ms	18472 KiB

dreaming

#include "dreaming.h"
#include <bits/stdc++.h>
#define MAX 100001
#define INF INT_MAX
#define MOD 1000000007
#define mp make_pair
#define mt make_tuple
#define pb push_back
#define ins insert
#define ff first
#define ss second
#define gett(x,m) get<m>(x)
#define all(a) a.begin(),a.end()
#define lb(a,b) lower_bound(all(a),b)
#define ub(a,b) upper_bound(all(a),b)
#define sortv(a) sort(all(a))
#define sorta(a,sz) sort(a,a+sz)
#define inputar(a,b){\
    for(int i=0;i<b;i++){\
        cin >> a[i];\
    }\
}
#define inputvec(a,b){\
    for(int i=0;i<b;i++){\
        ll num;\
        cin >> num;\
        a.pb(num);\
    }\
}
#define outputar(a,b){\
    for(int i=0;i<b;i++){\
        cout << a[i] << " ";\
    }\
    cout << "\n";\
}
#define outputvec(a){\
    for(auto x:a){\
        cout << x << " ";\
    }\
    cout << "\n";\
}
#define reset(a,n,v){\
    for(int i=0;i<n;i++){\
        a[i]=v;\
    }\
}
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef tuple<ll,ll,ll> tll;
typedef pair<ll,ll> pll;
typedef pair<int,int> pii;
typedef double db;
typedef long double ldb;
inline void USACO(string filename){
  freopen((filename+".in").c_str(),"r",stdin);
  freopen((filename+".out").c_str(),"w",stdout);
}
int h;
bool used[MAX];
int dist[MAX];
int dist2[MAX];
int maxdist1[MAX];
pair<pii,pii> maxdist[MAX];
vector<vector<pii>> g;
int b[MAX];
vector<int> e;
void dfs(int v,int prev){ 
    e.pb(v);
	used[v]=true;
	for(auto x:g[v]){
		if(x.ff==prev){
			continue;
		}
		dist[x.ff]=dist[v]+x.ss;
		dfs(x.ff,v);
	}
}
void dfs4(int v,int prev){ 
	for(auto x:g[v]){
		if(x.ff==prev){
			continue;
		}
		dist2[x.ff]=dist2[v]+x.ss;
		dfs4(x.ff,v);
	}
}
void dfs1(int v,int prev){ 
	used[v]=true;
	maxdist1[v]=dist[v];
	for(auto x:g[v]){
		if(x.ff==prev){
			continue;
		}
		dfs1(x.ff,v);
		maxdist1[v]=max(maxdist1[v],maxdist1[x.ff]);
	}
}
void dfs2(int v,int prev){ 
	used[v]=true;
	maxdist[v]=mp(mp(-INF,-INF),mp(-INF,-INF));
	for(auto x:g[v]){
		if(x.ff==prev){
			continue;
		}
		if(maxdist1[x.ff]>maxdist[v].ff.ff){
			maxdist[v].ss=max(maxdist[v].ss,maxdist[v].ff);
			maxdist[v].ff=mp(maxdist1[x.ff],x.ff);
		}
		else if(maxdist1[x.ff]>maxdist[v].ss.ff){
			maxdist[v].ss=mp(maxdist1[x.ff],x.ff);
		}
		dfs2(x.ff,v);
	}
}
void dfs3(int v,int prev){ 
	int h1=0;
	h1=max(h1,maxdist1[v]-dist[v]);
	if(prev!=-1){
		pair<pii,pii> p1=maxdist[prev]; 
		pii p2,p3; 
		p2=p1.ff; 
		p3=p1.ss; 
		b[v]=b[prev]+dist[v]-dist[prev];
		if(p2.ss!=v && p2.ff!=-INF){
			b[v]=max(b[v],p2.ff+dist[v]-2*dist[prev]);
		}
		else if(p3.ff!=-INF){
			b[v]=max(b[v],p3.ff+dist[v]-2*dist[prev]);
		}
		h1=max(h1,b[v]);
	}
	h=min(h,h1);
	used[v]=true;
	for(auto x:g[v]){
		if(x.ff==prev){
			continue;
		}
		dfs3(x.ff,v);
	}
}
int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
	int res;
	g.resize(N);
	for(int i=0;i<M;i++){
		g[A[i]].pb(mp(B[i],T[i])); 
		g[B[i]].pb(mp(A[i],T[i]));
	} 
	int maxd=0;
	for(int i=0;i<N;i++){
		if(!used[i]){
		    e.clear();
			dfs(i,-1);
			int maxd1=0;
			int maxd2=0;
			int ind=0;
			for(auto x:e){
			    if(dist[x]>maxd1){
			        maxd1=dist[x]; 
			        ind=x;
			    }
			}
		    dfs4(ind,-1);
		    for(auto x:e){
		        maxd2=max(maxd2,dist2[x]);
		    }
		    maxd=max(maxd,maxd2);
		}
	}
	memset(used,false,sizeof(used));
	for(int i=0;i<N;i++){
		if(!used[i]){
			dfs1(i,-1);
		}
	}
	memset(used,false,sizeof(used));
	for(int i=0;i<N;i++){
		if(!used[i]){
			dfs2(i,-1);
		}
	}
	memset(used,false,sizeof(used));
	vector<int> c; 
	for(int i=0;i<N;i++){
		if(!used[i]){
			h=INF;
			dfs3(i,-1); 
			c.pb(h);
		}
	}
	sortv(c);
	reverse(all(c));
	if(c.size()==1){
		res=c[0];
	}
	else{
		res=c[0]+c[1]+L;
	}
	if(c.size()>2){
		res=max(res,c[1]+c[2]+2*L);
	}
	res=max(maxd,res);
	return res;
}
/*
int main(){
	int n,m,k; 
	cin >> n >> m >> k;
	int A[m],B[m],T[m];
	for(int i=0;i<m;i++){
		cin >> A[i] >> B[i] >> T[i];
	}
	cout << travelTime(n,m,k,A,B,T);
}
*/

• Subtask 1: 14 / 14
• Subtask 2: 10 / 10
• Subtask 3: 23 / 23
• Subtask 4: 18 / 18
• Subtask 5: 12 / 12
• Subtask 6: 0 / 23