Submission #941867

#	Time	Username	Problem	Language	Result	Execution time	Memory
941867		May27_th	Robot (JOI21_ho_t4)	C++17	0 / 100	3099 ms	1077652 KiB

Main

#include<bits/stdc++.h>
#define taskname "A"
using namespace std;

void World_Final();
void Solve();

int main(){
    ios_base::sync_with_stdio(false); cin.tie(nullptr);
    if (fopen(taskname".in", "r")) {
        freopen(taskname".in", "r", stdin);
        freopen(taskname".out", "w", stdout);
    }
    World_Final();
}

void World_Final(){
    int Tests = 1;
    //cin >> Tests;
    for (int i = 1; i <= Tests; i ++) {
        //cout << i << "\n";
        Solve();
    }
}

const int MAXN = 2e5 + 10;
const int64_t INF = 1e18;
int N, M;
struct Road {
    int v, c; int64_t p;
    Road (int _v, int _c, int64_t _p) : v(_v), c(_c), p(_p) {};
}; vector<Road> G[MAXN]; pair<int, int64_t> par[MAXN]; int64_t f[MAXN];
map<int, int64_t> color[MAXN], sum[MAXN];
void Solve(){
    cin >> N >> M;
    for (int i = 1; i <= M; i ++) {
        int u, v, c; int64_t p; cin >> u >> v >> c >> p;
        G[u].push_back(Road(v, c, p));
        G[v].push_back(Road(u, c, p));
        sum[u][c] += p;
        sum[v][c] += p;
        color[u][c] ++;
        color[v][c] ++;
    }
    for (int i = 1; i <= N; i ++) {
        f[i] = INF;
        par[i] = make_pair(0, 0);
    } f[1] = 0;
    priority_queue<pair<int64_t, int>> pq; pq.push(make_pair(0, 1));
    while (!pq.empty()) {
        int64_t d; int u; tie(d, u) = pq.top(); pq.pop();
        if (-d != f[u]) continue;
        for (auto [v, c, p] : G[u]) {
            int cnt = color[u][c] - (par[u].first == c);
            int64_t w = sum[u][c] - p - (par[u].first == c ? par[u].second : 0);
            if (w > p) w = p;
            if (cnt <= 1) w = 0;
            if (f[v] > f[u] + w) {
                f[v] = f[u] + w;
                pq.push(make_pair(-f[v], v));
                if(w != 0) par[v] = make_pair(c, p);
            }
        }
    }
    cout << (f[N] == INF ? -1 : f[N]);
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:11:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 |         freopen(taskname".in", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:12:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |         freopen(taskname".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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