Submission #381160

#	Time	Username	Problem	Language	Result	Execution time	Memory
381160		usachevd0	Robot (JOI21_ho_t4)	C++14	100 / 100	1739 ms	96792 KiB

Main

#include <bits/stdc++.h>

using namespace std;

#define fi first
#define se second
#define mp make_pair
#define pb push_back
#define all(a) (a).begin(), (a).end()
using ll = long long;
using ull = unsigned long long;
using pii = pair<int, int>;
using pil = pair<int, ll>;
using pli = pair<ll, int>;
using pll = pair<ll, ll>;
using ld = long double;
template<typename T1, typename T2> bool chkmin(T1 &x, T2 y) { return y < x ? (x = y, true) : false; }
template<typename T1, typename T2> bool chkmax(T1 &x, T2 y) { return y > x ? (x = y, true) : false; }
void debug_out() { cerr << endl; }
template<typename T1, typename... T2> void debug_out(T1 A, T2... B) { cerr << ' ' << A; debug_out(B...); }
template<typename T> void mdebug_out(T* a, int n) { for (int i = 0; i < n; ++i) cerr << a[i] << ' '; cerr << endl; }
#ifdef DEBUG
    #define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
    #define mdebug(a, n) cerr << #a << ": ", mdebug_out(a, n)
#else
    #define debug(...) 1337
    #define mdebug(a, n) 1337
#endif
template<typename T> ostream& operator << (ostream& stream, const vector<T> &v) { for (auto x : v) stream << x << ' '; return stream; }
template<typename T1, typename T2> ostream& operator << (ostream& stream, const pair<T1, T2>& p) { return stream << p.first << ' ' << p.second; }

#define int ll

const ll INF64 = 1e18;
const int N = 100005;
int n, m;
struct Edge
{
    int from, to, t;
    ll c;

    Edge() {}
    Edge(int _from, int _to, int _t, ll _c): from(_from), to(_to), t(_t), c(_c) {}
};
vector<Edge> G[N];

void add_edge(int a, int b, int t, ll c)
{
    G[a].emplace_back(a, b, t, c);
    G[b].emplace_back(b, a, t, c);
}

map<pii, int> ctp;

int types[N];
vector<int> rtp[N];
int idxt[2 * N];

vector<vector<Edge>> GT[N];

vector<ll> sumC[N];
vector<ll> dist[N];
          
signed main()
{
#ifdef DEBUG
    freopen("in", "r", stdin);
#endif
    ios::sync_with_stdio(0);
    cin.tie(0);

    cin >> n >> m;
    for (int i = 1; i <= m; ++i)
    {
        int a, b, t, c;
        cin >> a >> b >> t >> c;
        add_edge(a, b, t, c);
    }
    for (int v = 1; v <= n; ++v)
    {
        types[v] = 0;
        rtp[v] = {-1};
        for (auto& e : G[v])
            if (!idxt[e.t])
            {
                ++types[v];
                ctp[{v, e.t}] = idxt[e.t] = types[v];
                rtp[v].push_back(e.t);
            }

        GT[v].resize(types[v] + 1);
        for (auto e : G[v])
            GT[v][idxt[e.t]].push_back(e);

        sumC[v].assign(types[v] + 1, 0);
        for (auto& e : G[v])
            sumC[v][idxt[e.t]] += e.c;

        for (auto& e : G[v])
            idxt[e.t] = 0;
    }
    /*for (int v = 1; v <= n; ++v)
    {
        debug(v);
        debug(rtp[v]);
    }*/
    for (int v = 1; v <= n; ++v)
        dist[v].assign(types[v] + 1, INF64);
    dist[1][0] = 0;
    multiset<pair<ll, pii>> q;
    q.insert({0, {1, 0}});
    while (!q.empty())
    {
        ll d = q.begin()->fi;
        int v = q.begin()->se.fi;
        int ct = q.begin()->se.se;
        q.erase(q.begin());
        if (d != dist[v][ct]) continue;

        if (ct == 0)
        {
            for (auto& e : G[v])
            {
                int u = e.to;
                int ct = ctp[{v, e.t}];
                if (chkmin(dist[u][0], d + min(e.c, sumC[v][ct] - e.c)))
                    q.insert({dist[u][0], {u, 0}});
                int ctu = ctp[{u, e.t}];
                if (chkmin(dist[u][ctu], d))
                    q.insert({dist[u][ctu], {u, ctu}});
            }
        }
        else
        {
            int t = rtp[v][ct];
            for (auto& e : GT[v][ct])
            {
                if (e.t == t)
                {
                    int u = e.to;
                    int ctu = ctp[{u, t}];
                    if (chkmin(dist[u][0], d + sumC[v][ct] - e.c))
                        q.insert({dist[u][0], {u, 0}});
                }
            }
        }
    }
    cout << (dist[n][0] >= INF64 ? -1 : dist[n][0]) << '\n';

    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:141:25: warning: unused variable 'ctu' [-Wunused-variable]
  141 |                     int ctu = ctp[{u, t}];
      |                         ^~~

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