Submission #1184245

#	Time	Username	Problem	Language	Result	Execution time	Memory
1184245		ivaziva	Dreaming (IOI13_dreaming)	C++20	32 / 100	37 ms	19128 KiB

dreaming

#include <bits/stdc++.h>
#include "dreaming.h"

using namespace std;

#define MAXN 100001

long long brkomp=0,timer=1,slucaj=-1;
vector<pair<long long,long long>> adj[MAXN];
long long komponenta[MAXN],dist[MAXN];
long long tin[MAXN],tout[MAXN],fenw[MAXN+1];
vector<long long> nodes[MAXN];
vector<long long> answers;

void dfs(long long node,long long pret)
{
    komponenta[node]=brkomp;nodes[brkomp].push_back(node);
    for (pair<long long,long long> par:adj[node])
    {
        int sled=par.first,w=par.second;if (sled==pret) continue;
        dist[sled]=dist[node]+w;dfs(sled,node);
    }
}

void dfs1(long long node,long long pret)
{
    tin[node]=timer;timer++;
    for (pair<long long,long long> par:adj[node])
    {
        int sled=par.first,w=par.second;if (sled==pret) continue;
        dist[sled]=dist[node]+w;dfs1(sled,node);
    }
    tout[node]=timer-1;
}

void update(long long pos,long long val)
{
    for (long long i=pos;i<=timer+1;i+=i&(-i)) fenw[i]+=val;
}

long long query(long long pos)
{
    long long sum=0;
    for (long long i=pos;i>0;i-=i&(-i)) sum+=fenw[i];
    return sum;
}

void resi(long long komp,long long n)
{
    long long maxdist=0,maxnode=nodes[komp][0];
    for (long long node:nodes[komp])
    {
        if (dist[node]>maxdist) {maxdist=dist[node];maxnode=node;}
    }
    timer=1;dist[maxnode]=0;dfs1(maxnode,0);long long len=0,sol=len;
    for (long long i=1;i<=timer+1;i++) fenw[i]=0;
    for (long long node:nodes[komp]) {len=max(len,dist[node]);sol=len;}
    for (long long node:nodes[komp])
    {
        if (dist[node]==len) update(tin[node],1);
    }
    for (long long node:nodes[komp])
    {
        long long value=max(dist[node],len-dist[node]);if (value>=sol) continue;
        if (value==dist[node]) {sol=min(sol,value);continue;}
        long long broj=query(tout[node])-query(tin[node]-1);if (broj>0) sol=min(sol,value);
    }
    slucaj=max(slucaj,len);answers.push_back(sol);
}

int travelTime(int n,int m,int l,int a[],int b[],int t[])
{
    for (long long i=0;i<m;i++) {long long node1=a[i]+1,node2=b[i]+1,weight=t[i];adj[node1].push_back({node2,weight});adj[node2].push_back({node1,weight});}
    for (long long node=1;node<=n;node++)
    {
        if (komponenta[node]==0) {brkomp++;dfs(node,0);}
    }
    for (long long komp=1;komp<=brkomp;komp++) resi(komp,n);
    sort(answers.begin(),answers.end());long long ans=slucaj;
    if (answers.size()!=1) ans=max(ans,answers[answers.size()-1]+answers[answers.size()-2]+l);
    if (answers.size()>=3) ans=max(ans,answers[answers.size()-2]+answers[answers.size()-3]+2*l);
    return ans;
}

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