제출 #383556

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
383556		valerikk	Robot (JOI21_ho_t4)	C++17	100 / 100	1295 ms	155216 KiB

Main

#include <bits/stdc++.h>
using namespace std;
#define ll long long 
const ll INF = 1e18;
const int N = 101010, M = 202020;
const int V = 2020202;

int n, m;
struct edge {
    int a, b, c;
    ll p;
} e[2 * M];
vector<ll> sum[N];
vector<pair<ll, int>> g[V];
int cnt;
ll d[V];
vector<int> cs[N], vv[N];
int an[N], sz[N];

void go(int st) {
    for (int i = 0; i < cnt; i++) d[i] = INF;
    priority_queue<pair<ll, int>, vector<pair<ll, int>>, greater<pair<ll, int>>> q;
    d[st] = 0;
    q.push({d[st], st});
    while (!q.empty()) {
        auto t = q.top();
        q.pop();
        int v = t.second;
        if (t.first != d[v]) continue;
        for (auto p : g[v]) {
            ll w = p.first;
            int u = p.second;
            //cout << w << " " << u << "\n";
            if (d[v] + w < d[u]) {
                d[u] = d[v] + w;
                q.push({d[u], u});
            }
        }
    }
}

int getpos(int v, int c) {
    return lower_bound(cs[v].begin(), cs[v].end(), c) - cs[v].begin();
}

int main() {
#ifdef LOCAL
    freopen("input.txt", "r", stdin);
#endif
    ios::sync_with_stdio(false);
    cin.tie(0);
    cin >> n >> m;
    for (int i = 0; i < m; i++) {
        cin >> e[i].a >> e[i].b >> e[i].c >> e[i].p;
        e[i].a--;
        e[i].b--;
        e[i].c--;
        e[i + m] = e[i];
        swap(e[i + m].a, e[i + m].b);
    }
    
    for (int i = 0; i < 2 * m; i++) cs[e[i].a].push_back(e[i].c);
    cnt = 4 * m;
    for (int i = 0; i < n; i++) {
        sort(cs[i].begin(), cs[i].end());
        cs[i].erase(unique(cs[i].begin(), cs[i].end()), cs[i].end());
        sz[i] = cs[i].size();
        sum[i].resize(sz[i]);
        for (int j = 0; j < sz[i]; j++) sum[i][j] = 0;
        vv[i].resize(sz[i]);
        for (int j = 0; j < sz[i]; j++) vv[i][j] = cnt++;
        an[i] = cnt++;
    }
    for (int i = 0; i < 2 * m; i++) {
        int pos = getpos(e[i].a, e[i].c);
        sum[e[i].a][pos] += e[i].p;
    }
    
    for (int i = 0; i < 2 * m; i++) {
        //cout << e[i].a << " " << e[i].b << " " << e[i].c << " " << e[i].p << "\n";
        int pos = getpos(e[i].a, e[i].c);
        ll s = sum[e[i].a][pos] - e[i].p;
        g[an[e[i].a]].push_back({s, i});
        g[an[e[i].a]].push_back({0, i + 2 * m});
        g[vv[e[i].a][pos]].push_back({s, i});
        
        g[i + 2 * m].push_back({e[i].p, an[e[i].b]});
        g[i].push_back({0, an[e[i].b]});
        
        pos = getpos(e[i].b, e[i].c);
        g[i + 2 * m].push_back({0, vv[e[i].b][pos]});
    }
    
    int st = an[0], fin = an[n - 1];
    go(st);
    if (d[fin] == INF) {
        cout << "-1\n";
    } else cout << d[fin] << "\n";
    return 0;
}

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