Submission #245099

#	Time	Username	Problem	Language	Result	Execution time	Memory
245099		uacoder123	Commuter Pass (JOI18_commuter_pass)	C++14	100 / 100	846 ms	28668 KiB

commuter_pass

#include <bits/stdc++.h>
using namespace std;
#define F first
#define S second
#define FOR(i,a,b) for (auto i = (a); i <= (b); ++i)
#define NFOR(i,a,b) for(auto i = (a); i >= (b); --i)
#define all(x) (x).begin(), (x).end()
#define sz(x) int(x.size())
#define mp(i,a) make_pair(i,a)
#define pb(a) push_back(a)
#define bit(x,b) (x&(1LL<<b))
 
typedef long long int lli;
typedef pair <lli,lli> ii;
typedef pair <lli,ii> iii;
typedef vector <lli> vi;
vector<ii> al[100001];
lli dis[100001][4];
int vis[100001]={};
lli ans,t;
iii arr[100001];
void dij(lli so,lli ty)
{
  set<ii>s;
  s.insert(mp(0*1ll,so));
  while(s.size()!=0)
  {
    ii v=(*s.begin());
    s.erase(s.begin());
    dis[v.S][ty]=v.F;
    for(lli i=0;i<al[v.S].size();++i)
    {
      if(dis[al[v.S][i].F][ty]==-1 or dis[al[v.S][i].F][ty]>v.F+al[v.S][i].S)
      {
        s.erase(mp(dis[al[v.S][i].F][ty],al[v.S][i].F));
        dis[al[v.S][i].F][ty]=al[v.S][i].S+v.F;
        s.insert(mp(dis[al[v.S][i].F][ty],al[v.S][i].F));
      }
    }
  }
}
void dfs(int s)
{
  vis[s]=1;
  if(s==t)
  {
    arr[t]=mp(dis[t][2]+dis[t][3],mp(dis[t][2],dis[t][3]));
    return;
  }
  for(int i=0;i<al[s].size();++i)
  {
    if(dis[s][0]+al[s][i].S+dis[al[s][i].F][1]!=dis[t][0])
      continue;
    if(!vis[al[s][i].F])
      dfs(al[s][i].F);
    arr[s].S.F=min(arr[s].S.F,min(arr[al[s][i].F].S.F,dis[s][2]));
    arr[s].S.S=min(arr[s].S.S,min(arr[al[s][i].F].S.S,dis[s][3]));
    arr[s].F=min(arr[s].F,min(arr[al[s][i].F].F,min(dis[s][2]+dis[s][3],min(dis[s][2]+arr[al[s][i].F].S.S,dis[s][3]+arr[al[s][i].F].S.F))));
  }
}
int main()
{
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  lli test=1;
  for(;test>0;--test)
  {
    lli n,m,s,u,v;
    cin>>n>>m>>s>>t>>u>>v;
    for(lli i=0;i<m;++i)
    {
      lli f,s,w;
      cin>>f>>s>>w;
      al[f].pb(mp(s,w));
      al[s].pb(mp(f,w));
    }
    memset(dis,-1,sizeof(dis));
    dij(s,0);
    dij(t,1);
    dij(u,2);
    dij(v,3);
    for(int i=0;i<=n;++i)
      arr[i]=mp(1000000000000000000,mp(1000000000000000000,1000000000000000000));
    dfs(s);
    ans=dis[v][2];
    cout<<min(ans,arr[s].F)<<endl;
  }
  return(0);
}

Compilation message (stderr)

commuter_pass.cpp: In function 'void dij(lli, lli)':
commuter_pass.cpp:31:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(lli i=0;i<al[v.S].size();++i)
                 ~^~~~~~~~~~~~~~~
commuter_pass.cpp: In function 'void dfs(int)':
commuter_pass.cpp:50:16: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   for(int i=0;i<al[s].size();++i)
               ~^~~~~~~~~~~~~

• Subtask 1: 16 / 16
• Subtask 2: 15 / 15
• Subtask 3: 24 / 24
• Subtask 4: 45 / 45