Submission #825839

#	Time	Username	Problem	Language	Result	Execution time	Memory
825839		AmirElarbi	Olympic Bus (JOI20_ho_t4)	C++14	0 / 100	1 ms	468 KiB

ho_t4

#include<bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#define INF 1e9
#define ve vector
#define vi ve<int>
#define ii pair<int,int>
#define vii ve<ii>
#define pb push_back
#define fi first
#define se second
#define ll long long
using namespace __gnu_pbds;
using namespace std;
const int nax = 400+5;
const int kax = 2+5;
const int MOD = 1e9+7;
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
vi adj[nax];
int x[nax], y[nax], c[nax], d[nax]; 
int main(){
    ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
    int n,m;
    cin >> n >> m;
    for (int i = 0; i < m; ++i)
    {
        cin >> x[i] >> y[i] >> c[i] >> d[i];
        adj[x[i]].pb(i);
    }
    int aff = INF;
    for (int i = 0; i < m; ++i)
    {
        priority_queue<ii, vii, greater<ii>> pq;
        vi dist(n+1, INF);
        dist[1] = 0;
        pq.push({0, 1});
        while(!pq.empty()){
            int cst = pq.top().fi, u = pq.top().se;
            pq.pop();
            if(dist[u] != cst) continue;
            for(auto j : adj[u]){
                if(j == i) continue;
                if(dist[y[j]] > c[j] + dist[u]){
                    dist[y[j]] = c[j] + dist[u];
                    pq.push({dist[y[j]], y[j]});
                }
            }
            if(u == y[i] && dist[x[i]] > d[i] + c[i] + dist[u]) {
                dist[x[i]] = d[i] + c[i] + dist[u];
                pq.push({dist[x[i]], x[i]});
            }
        }
        int ans = dist[n];
        dist.clear();
        dist.assign(n+1,INF);
        dist[n] = 0;
        pq.push({0,n});
        while(!pq.empty()){
            int cst = pq.top().fi, u = pq.top().se;
            pq.pop();
            if(dist[u] != cst) continue;
            for(auto j : adj[u]){
                if(j == i) continue;
                if(dist[y[j]] > c[j] + dist[u]){
                    dist[y[j]] = c[j] + dist[u];
                    pq.push({dist[y[j]], y[j]});
                }
            }
            if(u == y[i] && dist[x[i]] > d[i] + c[i] + dist[u]) {
                dist[x[i]] = d[i] + c[i] + dist[u];
                pq.push({dist[x[i]], x[i]});
            }
        }
        ans += dist[1];
        aff = min(aff, ans);
    }
    if(aff == INF) cout << -1 << endl;
    else cout << aff << endl;
}

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