Submission #593423

#	Time	Username	Problem	Language	Result	Execution time	Memory
593423		piOOE	Robot (JOI21_ho_t4)	C++17	0 / 100	365 ms	34840 KiB

Main

#include <bits/stdc++.h>

using namespace std;

using ll = long long;

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int n, m;
    cin >> n >> m;
    vector<vector<pair<int, int>>> g(n); //to, weight
    vector<int> c(m), p(m), a(m), b(m);
    vector<map<int, int>> cnt(n);
    for (int i = 0; i < m; ++i) {
        cin >> a[i] >> b[i] >> c[i] >> p[i];
        --a[i], --b[i];
        ++cnt[a[i]][c[i]];
        ++cnt[b[i]][c[i]];
    }
    for (int i = 0; i < m; ++i) {
        if (cnt[a[i]][c[i]] == 1) {
            g[a[i]].emplace_back(b[i], 0);
        } else {
            g[a[i]].emplace_back(b[i], p[i]);
        }
        if (cnt[b[i]][c[i]] == 1) {
            g[b[i]].emplace_back(a[i], 0);
        } else {
            g[b[i]].emplace_back(a[i], p[i]);
        }
    }
    const ll inf = 1e18;
    vector<ll> dist(n, inf);
    dist[0] = 0;
    set<pair<ll, int>> st;
    st.insert({0, 0});
    while (!st.empty()) {
        auto [ww, v] = *st.begin();
        st.erase(st.begin());
        for (auto [to, w] : g[v]) {
            if (dist[to] > dist[v] + w) {
                st.erase({dist[to], to});
                dist[to] = dist[v] + w;
                st.insert({dist[to], to});
            }
        }
    }
    cout << (dist[n - 1] == inf ? -1 : dist[n - 1]);
    return 0;
}

• Subtask 1: 0 / 34
• Subtask 2: 0 / 24
• Subtask 3: 0 / 42