Submission #66576

#	Time	Username	Problem	Language	Result	Execution time	Memory
66576		Vahan	Dreaming (IOI13_dreaming)	C++17	100 / 100	107 ms	15352 KiB

dreaming

#include "dreaming.h"
#include<vector>
#include<fstream>
#include<iostream>
#include<algorithm>
using namespace std;
vector<pair<int,int > > g[200000];
int u[200000],x[200000],d[200000],pa[200000],mh,ind,t,pat;
void dfs(int v,int p)
{
    u[v]=1;
    for(int i=0;i<g[v].size();i++)
    {
        int to =g[v][i].first;
        int her=g[v][i].second;
        if(to==p)
            continue;
        d[to]=d[v]+ her;
        pa[to]=v;
        if(d[to]>mh)
        {
            mh=d[to];
            ind=to;
        }
        dfs(to,v);
    }
}
int travelTime(int N, int M, int L, int A[], int B[], int T[]) {
    for(int i=0;i<M;i++)
    {
        g[A[i]].push_back(make_pair(B[i],T[i]));
        g[B[i]].push_back(make_pair(A[i],T[i]));
    }
    for(int i=0;i<N;i++)
    {
        if(u[i]==0)
        {
            d[i]=0;
            mh=0;
            ind=i;
            dfs(i,-1);
            int a=ind;
            d[a]=0;
            mh=0;
            ind=a;
            dfs(a,-1);
            int b=ind;
            int e=b;
            int l=mh;
            pat=max(pat,mh);
            while(e!=a)
            {
                l=min(l,max(mh-d[e],d[e]));
                e=pa[e];
            }
            x[t]=l;
            t++;
        }
    }
    sort(x,x+t);
    pat=max(pat,x[t-1]);
    if(t>=2)
        pat=max(pat,x[t-1]+x[t-2]+L);
    if(t>=3)
        pat=max(pat,x[t-2]+x[t-3]+2*L);
    return pat;
}

Compilation message (stderr)

dreaming.cpp: In function 'void dfs(int, int)':
dreaming.cpp:12:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0;i<g[v].size();i++)
                 ~^~~~~~~~~~~~

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