Submission #1292396

#	Time	Username	Problem	Language	Result	Execution time	Memory
1292396		dungnt	Robot (JOI21_ho_t4)	C++20	100 / 100	130 ms	15480 KiB

Main

#include<bits/stdc++.h>
#define ll long long
#define pii pair<ll, int>
using namespace std;

const int N = 100000 + 5;
const int M = 200000 + 5;
const ll INF = 1e18;

struct E
{
    int v, c, w;
    E(){}
    E(int _v, int _c, int _w)
    {
        v = _v;
        c = _c;
        w = _w;
    }
};

int n, m;
vector<E> adj[N];
ll d[N], sum[M], best[M];

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0); cout.tie(0);
    #define name "baitap"
    if(fopen(name".inp", "r"))
    {
        freopen(name".inp", "r", stdin);
        freopen(name".out", "w", stdout);
    }
    cin >> n >> m;
    for(int i = 1; i <= m; i++)
    {
        int u, v, c, w;
        cin >> u >> v >> c >> w;
        adj[u].push_back({v, c, w});
        adj[v].push_back({u, c, w});
    }
    for(int i = 1; i <= n; i++)
        d[i] = INF;
    for(int i = 1; i <= m; i++)
        best[i] = INF;
    priority_queue<pii, vector<pii>, greater<pii>> pq;
    d[1] = 0;
    pq.push({0, 1});
    while(!pq.empty())
    {
        auto [du, u] = pq.top();    pq.pop();
        if(du != d[u])  continue;
        for(auto [v, c, w] : adj[u])
        {
            sum[c] += w;
            if(best[c] > d[v])  best[c] = d[v];
        }
        for(auto [v, c, w] : adj[u])
        {
            ll t1 = w < sum[c] - w ? w : sum[c] - w;
            ll nd1 = du + t1;
            if(d[v] > nd1)
            {
                d[v] = nd1;
                pq.push({nd1, v});
            }
            ll nd2 = best[c] + sum[c] - w;
            if(d[v] > nd2)
            {
                d[v] = nd2;
                pq.push({nd2, v});
            }
        }
        for(auto [v, c, w] : adj[u])
        {
            sum[c] = 0;
            best[c] = INF;
        }
    }
    if(d[n] == INF) cout << -1;
    else    cout << d[n];
}

Compilation message (stderr)

Main.cpp: In function 'int main()':
Main.cpp:33:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   33 |         freopen(name".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
Main.cpp:34:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   34 |         freopen(name".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

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