Submission #416014

#	Time	Username	Problem	Language	Result	Execution time	Memory
416014		meatrow	Robot (JOI21_ho_t4)	C++17	0 / 100	3078 ms	62180 KiB

Main

// #pragma GCC target ("avx2")
// #pragma GCC optimization ("O3")
#include <bits/stdc++.h>

using namespace std;

using ll = long long;
using ld = long double;

const int MOD = 1e9 + 7;

ll binpow(ll a, ll p, int mod = MOD) {
    ll res = 1;
    while (p) {
        if (p & 1) {
            (res *= a) %= mod;
        }
        p >>= 1;
        (a *= a) %= mod;
    }
    return res;
}

ll gcd(ll a, ll b) {
    return b == 0 ? a : gcd(b, a % b);
}

struct Edge {
    int a, b, color, price;
};

void solve() {
    int n, m;
    cin >> n >> m;
    vector<Edge> edges(m);
    vector<vector<int>> g(n + 1);
    vector<map<int, int>> rev(n + 1);
    for (int i = 0; i < m; i++) {
        cin >> edges[i].a >> edges[i].b >> edges[i].color >> edges[i].price;
        g[edges[i].a].push_back(i);
        g[edges[i].b].push_back(i);
        rev[edges[i].a][i] = g[edges[i].a].size() - 1;
        rev[edges[i].b][i] = g[edges[i].b].size() - 1;
    }
    
    vector<vector<ll>> dist(n + 1);
    for (int i = 1; i <= n; i++) {
        dist[i].assign(g[i].size() * 2 + 1, 1e18);
    }
    dist[1][0] = 0;
    set<pair<ll, pair<int, int>>> setik;
    setik.insert({0, {1, 0}});
    while (!setik.empty()) {
        int v, from;
        tie(v, from) = setik.begin()->second;
        setik.erase(setik.begin());
        map<int, ll> sum;
        for (int i = 0; i < g[v].size(); i++) {
            auto& edge = edges[g[v][i]];
            if (from != i * 2 + 1) {
                sum[edge.color] += edge.price;
            }
        }
        for (int i = 0; i < g[v].size(); i++) {
            if (from == i * 2 + 1) continue;
            auto& edge = edges[g[v][i]];
            int to = edge.a ^ edge.b ^ v;
            int w = edge.price;
            int id = rev[to][g[v][i]];
            if (dist[v][from] + w < dist[to][id * 2 + 1]) {
                setik.erase({dist[to][id * 2 + 1], {to, id * 2 + 1}});
                dist[to][id * 2 + 1] = dist[v][from] + w;
                setik.insert({dist[to][id * 2 + 1], {to, id * 2 + 1}});
            }

            w = sum[edge.color] - edge.price;
            if (dist[v][from] + w < dist[to][id * 2]) {
                setik.erase({dist[to][id * 2], {to, id * 2}});
                dist[to][id * 2] = dist[v][from] + w;
                setik.insert({dist[to][id * 2], {to, id * 2}});
            }
        }
    }

    ll ans = *min_element(dist[n].begin(), dist[n].end());
    if (ans == 1e18) ans = -1;
    cout << ans << '\n';
}

int main() {
    ios::sync_with_stdio(false);
    cin.tie(nullptr);
    int T = 1;
    // cin >> T;
    for (int tc = 1; tc <= T; tc++) {
        // cout << "Case #" << tc << ": ";
        solve();
    }
    return 0;
}

Compilation message (stderr)

Main.cpp: In function 'void solve()':
Main.cpp:58:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   58 |         for (int i = 0; i < g[v].size(); i++) {
      |                         ~~^~~~~~~~~~~~~
Main.cpp:64:27: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   64 |         for (int i = 0; i < g[v].size(); i++) {
      |                         ~~^~~~~~~~~~~~~

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