Submission #890819

#	Time	Username	Problem	Language	Result	Execution time	Memory
890819		ByeWorld	Commuter Pass (JOI18_commuter_pass)	C++14	16 / 100	406 ms	41844 KiB

commuter_pass

#include <bits/stdc++.h>
#pragma GCC optimize("O3,unroll-loops")
#pragma GCC target("avx2,bmi,bmi2,lzcnt,popcnt")
#define bupol __builtin_popcount
#define int long long
#define ll long long
#define ld long double
#define fi first
#define se second
#define pb push_back
#define lf (id<<1)
#define rg ((id<<1)|1)
#define md ((l+r)>>1)
using namespace std;
const int MAXN = 2e5+5;
const int LOG = 20;
const int MOD = 1e9+7;
const int SQRT = 520;
const int INF = 1e18;
typedef pair<int,int> pii;
typedef pair<int,pii> ipii;

int n, m;
int s, t, x, y;
int u[MAXN], v[MAXN], c[MAXN];
vector <pii> adj[MAXN];
int dis[MAXN], di[MAXN];
bool ty[MAXN];
priority_queue<pii, vector<pii>, greater<pii>> pq;
map<pii,int> ma;

void dji(int sta){
    for(int i=1; i<=n; i++) dis[i] = INF;
    pq.push({0, sta});
    dis[sta] = 0;
    while(!pq.empty()){
        int tp = pq.top().se; int dist = pq.top().fi; pq.pop();
        if(dis[tp] < dist) continue;
        for(auto ed : adj[tp]){
            int nx = ed.fi; int wei = ed.se;
            if(dis[nx] > dist+wei){
                dis[nx] = dist+wei;
                pq.push({dis[nx], nx});
            }
        }
    }
} 
void dji2(int sta){
    for(int i=1; i<=n; i++) di[i] = INF;
    pq.push({0, sta});
    di[sta] = 0;
    while(!pq.empty()){
        int tp = pq.top().se; int dist = pq.top().fi; pq.pop();
        if(di[tp] < dist) continue;
        for(auto ed : adj[tp]){
            int nx = ed.fi; int wei = ed.se;
            if(di[nx] > dist+wei){
                di[nx] = dist+wei;
                pq.push({di[nx], nx});
            }
        }
    }
} 
signed main(){
    //ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
    cin >> n >> m;
    cin >> s >> t; cin >> x >> y;
    for(int i=1; i<=m; i++){
        cin >> u[i] >> v[i] >> c[i];
        if(u[i] > v[i]) swap(u[i], v[i]);
        ma[pii(u[i], v[i])] = i;
        adj[u[i]].pb({v[i], c[i]}); adj[v[i]].pb({u[i], c[i]});
    }
    dji(s); dji2(t);
    //cout << dis[t] << " dis\n";

    for(int i=1; i<=n; i++){
        if(dis[i]+di[i] == dis[t]) ty[i] = 1;
    }
    dji(y);

    int ans = INF;
    for(int i=1; i<=n; i++)
        if(ty[i]) ans = min(ans, dis[i]);
    cout << ans << '\n';
}

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