Submission #922797

#	Time	Username	Problem	Language	Result	Execution time	Memory
922797		vjudge1	Olympic Bus (JOI20_ho_t4)	C++17	0 / 100	508 ms	262144 KiB

ho_t4

#include <bits/stdc++.h>

#pragma GCC optimize("Ofast")
#pragma GCC target("avx2")

using namespace std;

#define ll long long
#define ld long double
#define pb push_back
#define pf push_front
#define pii pair<int,int>
#define all(v) v.begin(),v.end()
#define F first
#define S second
#define mem(a,i) memset(a,i,sizeof(a))
#define sz(s) (int)s.size()
#define int ll
#define y1 yy
#define ppb pop_back
#define gcd(a,b) __gcd(a,b)
#define in insert

const int dx[4]={-1,0,1,0};
const int dy[4]={0,-1,0,1};

const int inf=1e18;
const int N=5e4+100;
const int MAX=210;
const int mod=1e9+7;


int n,m;
vector<pair<int,pii>> g[MAX];
int d[MAX][N+N];
int d1[MAX][N+N];

void solve(){
  cin>>n>>m;
  for(int i=1;i<=m;i++){
    int u,v,c,d;
    cin>>u>>v>>c>>d;
    g[u].pb({v,{c,i+m}});
    g[v].pb({u,{c+d,i}});
  }
  {
    for(int i=1;i<=n;i++){
      for(int j=0;j<=m;j++){
        d[i][j]=inf;
      }
    }
    set<pair<int,pii>> st;
    for(int j=0;j<=m;j++){
      d[1][j]=0;
      st.in({d[1][j],{1,j}});
    }
    while(!st.empty()){
      int v=st.begin()->S.F;
      int r=st.begin()->S.S;
      st.erase(st.begin());
      for(auto to:g[v]){
        if(to.S.S>m){
          if(to.S.S-m==r)continue;
          if(d[to.F][r]>d[v][r]+to.S.F){
            st.erase({d[to.F][r],{to.F,r}});
            d[to.F][r]=d[v][r]+to.S.F;
            st.in({d[to.F][r],{to.F,r}});
          }
        }
        else{
          if(to.S.S!=r)continue;
          if(d[to.F][r]>d[v][r]+to.S.F){
            st.erase({d[to.F][r],{to.F,r}});
            d[to.F][r]=d[v][r]+to.S.F;
            st.in({d[to.F][r],{to.F,r}});
          }
        }
      }
    }
  }
  {
    for(int i=1;i<=n;i++){
      for(int j=0;j<=m;j++){
        d1[i][j]=inf;
      }
    }
    set<pair<int,pii>> st;
    for(int j=0;j<=m;j++){
      d1[n][j]=0;
      st.in({d1[n][j],{n,j}});
    }
    while(!st.empty()){
      int v=st.begin()->S.F;
      int r=st.begin()->S.S;
      st.erase(st.begin());
      for(auto to:g[v]){
        if(to.S.S>m){
          if(to.S.S-m==r)continue;
          if(d1[to.F][r]>d1[v][r]+to.S.F){
            st.erase({d1[to.F][r],{to.F,r}});
            d1[to.F][r]=d1[v][r]+to.S.F;
            st.in({d1[to.F][r],{to.F,r}});
          }
        }
        else{
          if(to.S.S!=r)continue;
          if(d1[to.F][r]>d1[v][r]+to.S.F){
            st.erase({d1[to.F][r],{to.F,r}});
            d1[to.F][r]=d1[v][r]+to.S.F;
            st.in({d1[to.F][r],{to.F,r}});
          }
        }
      }
    }
  }
  int ans=d[n][0]+d1[1][0];
  for(int i=1;i<=m;i++){
    ans=min(ans,d[n][i]+d1[1][i]);
  }
  if(ans<inf)cout<<ans<<"\n";
  else cout<<-1<<"\n";
}

main(){
  // freopen("prizes.in", "r", stdin);
  // freopen("prizes.out", "w", stdout);
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  cout.tie(0);
  int t=1;
  // cin>>t;
  while(t--){
    solve();
  }
}

Compilation message (stderr)

ho_t4.cpp:124:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
  124 | main(){
      | ^~~~

• Subtask 1: 0 / 5
• Subtask 2: 0 / 11
• Subtask 3: 0 / 21
• Subtask 4: 0 / 63