Submission #372501

#	Time	Username	Problem	Language	Result	Execution time	Memory
372501		iliccmarko	Commuter Pass (JOI18_commuter_pass)	C++14	31 / 100	478 ms	29588 KiB

commuter_pass

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define endl "\n"
#define INF 1000000000
#define LINF 10000000000000000LL
#define pb push_back
#define all(x) x.begin(), x.end()
#define len(s) (int)s.size()
#define test_case { int t; cin>>t; while(t--)solve(); }
#define single_case solve();
#define line cerr<<"----------"<<endl;
#define ios { ios_base::sync_with_stdio(false); cin.tie(NULL); cout.tie(NULL); cerr.tie(NULL); }
#define mod 1000000007LL
const int N = 2e5 + 5;
vector<pair<ll, ll> > g[N];
ll ds[N], dt[N], du[N], dv[N];
ll n, m, s, t, u, v;
int vidjen[N];
ll d[N];

void dijkstra(ll src, ll dis[])
{
    for(int i = 0;i<N;i++) dis[i] = LINF, vidjen[i] = 0;
    priority_queue<pair<ll, ll>, vector<pair<ll, ll> >, greater<pair<ll, ll> > > pq;
    dis[src] = 0;
    pq.push(make_pair(0, src));
    while(len(pq))
    {
        ll u = pq.top().second;
        pq.pop();
        if(vidjen[u]) continue;
        vidjen[u] = 1;
        for(auto x : g[u])
        {
            ll v = x.first;
            ll c = x.second;
            if(dis[v]>dis[u]+c)
            {
                dis[v] = dis[u] + c;
                pq.push(make_pair(dis[v], v));
            }
        }
    }
}

void dijkstra2(ll src, ll dis[])
{
    for(int i = 0;i<N;i++) dis[i] = LINF, vidjen[i] = 0;
    priority_queue<pair<ll, ll>, vector<pair<ll, ll> >, greater<pair<ll, ll> > > pq;
    dis[src] = 0;
    pq.push(make_pair(0, src));
    while(len(pq))
    {
        ll u = pq.top().second;
        pq.pop();
        if(vidjen[u]) continue;
        vidjen[u] = 1;
        for(auto x : g[u])
        {
            ll v = x.first;
            ll c = x.second;
            ll k = 0;
            if(ds[u]+dt[u]!=ds[t]) k = c;
            if(dis[v]>dis[u]+k)
            {
                dis[v] = dis[u] + k;
                if(ds[v]+dt[v]==ds[t]) continue;
                pq.push(make_pair(dis[v], v));
            }
        }
    }
}

bool cmp(int a, int b)
{
    return du[a] < du[b];
}

void dfs(ll u, ll x)
{
    vidjen[u] = 1;
    du[u] = min(du[u], x);
    for(auto W : g[u])
    {
        if(vidjen[W.first]==1||ds[W.first]+dt[W.first]!=ds[t]) continue;
        dfs(W.first, x);
    }
}

int main()
{
    ios
    cin>>n>>m>>s>>t>>u>>v;
    for(int i = 0;i<m;i++)
    {
        ll a, b, c;
        cin>>a>>b>>c;
        g[a].pb(make_pair(b, c));
        g[b].pb(make_pair(a, c));
    }
    dijkstra(s, ds);
    dijkstra(t, dt);
    dijkstra2(u, du);
    dijkstra2(v, dv);
    vector<ll> w;
    for(ll i = 1;i<=n;i++)
    {
        if(ds[i]+dt[i]==ds[t]) w.pb(i);
    }
    for(ll i = 0;i<N;i++) vidjen[i] = 0;
    sort(all(w), cmp);
    vector<ll> q;
    for(ll i = 1;i<=n;i++) if(ds[i]+dt[i]==ds[t]) q.pb(i);
    for(ll x : w)
    {
        if(vidjen[x]) continue;
        dfs(x, du[x]);
    }
    dijkstra(v, d);
    ll res = d[u];
    for(int i = 1;i<=n;i++)
        if(ds[i]+dt[i]==ds[t]) res = min(res, dv[i]+du[i]);

    cout<<res;






    return 0;
}

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