Submission #1268799

#	Time	Username	Problem	Language	Result	Execution time	Memory
1268799		bhnm	Commuter Pass (JOI18_commuter_pass)	C++20	15 / 100	2095 ms	27028 KiB

commuter_pass

#include<bits/stdc++.h>
#define ll long long
#define pll pair<long long,long long>
using namespace std;
const ll maxn = 2e5 + 5;
const ll mod = 1e9 + 7;
const ll base = 13;
const ll inf = 1e14;
ll n,m,x,y,z,s,t,u,v;
vector<pll>a[maxn];
ll dist[maxn][5];
ll ans;
ll best[maxn][5];
priority_queue<pll,vector<pll>,greater<pll>>pe;
void dijk(ll st,ll type)
{
    for(ll i = 1;i<=n;i++)
    {
        dist[i][type] = inf;
    }
    dist[st][type] = 0;
    pe.push({0,st});
    while(!pe.empty())
    {
        ll u = pe.top().second;
        ll cur = pe.top().first;
        pe.pop();
        if(dist[u][type] < cur)
        {
            continue;
        }
        for(pll v : a[u])
        {
            if(dist[v.first][type] > dist[u][type] + v.second)
            {
                dist[v.first][type] = dist[u][type] + v.second;
                pe.push({dist[v.first][type],v.first});
            }
        }
    }
}
void dfs(ll u)
{
    best[u][2] = dist[u][2];
    best[u][3] = dist[u][3];
    for(auto [v,w] : a[u])
    {
        if(dist[v][1] + w == dist[u][1])
        {
            dfs(v);
            best[u][2] = min(best[u][2],best[v][2]);
            best[u][3] = min(best[u][3],best[v][3]);
        }
    }
    ans = min(ans,min(best[u][2] + dist[u][3],best[u][3] + dist[u][2]));
}
void solve()
{
    cin>>n>>m>>s>>t>>u>>v;
    for(ll i = 1;i<=m;++i)
    {
        cin>>x>>y>>z;
        a[x].push_back({y,z});
        a[y].push_back({x,z});
    }
    dijk(s,1);
    dijk(u,2);
    dijk(v,3);
    ans = dist[u][3];
    dfs(t);
    cout<<ans;
}
int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    //freopen("BUS.INP","r",stdin);
    //freopen("BUS.OUT","w",stdout);
    ll t = 1;
    //cin>>t;
    while(t--)
    {
        solve();
    }
    return 0;
}

• Subtask 1: 0 / 16
• Subtask 2: 15 / 15
• Subtask 3: 0 / 24
• Subtask 4: 0 / 45