Submission #998597

#	Time	Username	Problem	Language	Result	Execution time	Memory
998597		pannenkoek	Commuter Pass (JOI18_commuter_pass)	C++17	31 / 100	180 ms	22236 KiB

commuter_pass

#include <bits/stdc++.h>
using namespace std;

#define rep(i, a, b) for(int i = (a); i < (b); i++)
#define pb push_back
#define fi first
#define se second

using ll = long long;
using ld = long double;
using pii = pair<ll, ll>;

const int MAXN = 1e5 + 5;
const ll inf = 1e18 + 5;
int n, m, s, t, u, v;
vector<pii> adj[MAXN];
set<pii> marked;
bool vis[MAXN];
ll dis1[MAXN], dis2[MAXN], dis3[MAXN], dis4[MAXN];

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cin >> n >> m >> s >> t >> u >> v;
    s--; t--; u--; v--;

    rep(i, 0, m){
        int a, b, c;
        cin >> a >> b >> c;
        a--; b--;
        adj[a].pb({b, c});
        adj[b].pb({a, c});
    }

    priority_queue<pii, vector<pii>, greater<pii>> pq;
    fill(dis1, dis1 + n, inf);
    dis1[s] = 0;
    pq.push({0, s});
    while(!pq.empty()){
        auto [d, cur] = pq.top();
        pq.pop();
        if(d > dis1[cur]) continue;
        for(auto [i, d2]: adj[cur]){
            if(d + d2 < dis1[i]){
                pq.push({d + d2, i});
                dis1[i] = d + d2;
            }
        }
    }
    fill(dis2, dis2 + n, inf);
    dis2[t] = 0;
    pq.push({0, t});
    while(!pq.empty()){
        auto [d, cur] = pq.top();
        pq.pop();
        if(d > dis2[cur]) continue;
        for(auto [i, d2]: adj[cur]){
            if(d + d2 < dis2[i]){
                pq.push({d + d2, i});
                dis2[i] = d + d2;
            }
        }
    }
    
    fill(dis3, dis3 + n, inf);
    dis3[u] = 0;
    pq.push({0, u});
    while(!pq.empty()){
        auto [d, cur] = pq.top();
        pq.pop();
        if(d > dis3[cur]) continue;
        for(auto [i, d2]: adj[cur]){
            if(dis1[cur] + dis2[i] + d2 == dis1[t]) d2 = 0;
            if(d + d2 < dis3[i]){
                pq.push({d + d2, i});
                dis3[i] = d + d2;
            }
        }
    }
    fill(dis4, dis4 + n, inf);
    dis4[u] = 0;
    pq.push({0, u});
    while(!pq.empty()){
        auto [d, cur] = pq.top();
        pq.pop();
        if(d > dis4[cur]) continue;
        for(auto [i, d2]: adj[cur]){
            if(dis2[cur] + dis1[i] + d2 == dis1[t]) d2 = 0;
            if(d + d2 < dis4[i]){
                pq.push({d + d2, i});
                dis4[i] = d + d2;
            }
        }
    }
    cout << min(dis3[v], dis4[v]) << "\n";

    return 0;
}

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