Submission #946159

#	Time	Username	Problem	Language	Result	Execution time	Memory
946159		AverageAmogusEnjoyer	Robot (JOI21_ho_t4)	C++17	100 / 100	422 ms	41620 KiB

Main

#include <bits/stdc++.h>
using namespace std;
using ll = long long;
template<class T> bool cmin(T &i, T j) { return i > j ? i=j,true:false; }
template<class T> bool cmax(T &i, T j) { return i < j ? i=j,true:false; }

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, m;
    cin >> n >> m;
    vector<map<int,vector<pair<int,int>>>> adj(n);
    for (int i=0,u,v,c,w;i<m;i++) {
        cin >> u >> v >> c >> w;
        --u,--v;
        adj[u][c].emplace_back(v,w);
        adj[v][c].emplace_back(u,w);
    }
    const ll inf = 1e18;
    vector<ll> dist(n,inf);
    dist[0] = 0;
    set<pair<ll,int>> q;
    q.emplace(0,0);
    while(!q.empty()) {
        int x=(*q.begin()).second;q.erase(q.begin());
        for (auto &edges: adj[x]) {
            if (edges.second.size()==1) {
                for (auto &[y,w]: edges.second) {
                    ll p=dist[y];
                    if (cmin(dist[y],dist[x])) {
                        q.erase(make_pair(p,y));
                        q.emplace(dist[y],y);
                    }
                }
                continue;
            }
            multiset<ll> dists;
            ll sum=0;
            for (auto &[y,w]: edges.second) {
                dists.insert(dist[y]);
                sum+=w;
            }
            for (auto &[y,w]: edges.second) {
                dists.erase(dists.find(dist[y]));
                ll d=min({dist[x]+w,
                            *dists.begin()+sum-w,
                                dist[x]+sum-w});
                ll p=dist[y];
                if (cmin(dist[y],d)) {
                    q.erase(make_pair(p,y));
                    q.emplace(d,y);
                }
                dists.insert(dist[y]);
            }
        }
    }
    cout << (dist[n-1]==inf?-1:dist[n-1]) << endl;
}

• Subtask 1: 34 / 34
• Subtask 2: 24 / 24
• Subtask 3: 42 / 42