Submission #553199

#	Time	Username	Problem	Language	Result	Execution time	Memory
553199		Tien_Noob	Evacuation plan (IZhO18_plan)	C++17	100 / 100	610 ms	55060 KiB

plan

//Make CSP great again
//Vengeance
#include <bits/stdc++.h>
#define TASK "TESTCODE"
#define Log2(x) 31 - __builtin_clz(x)
using namespace std;
const int N = 1e5;
priority_queue< pair<int, int>, deque<pair<int, int> > , greater<pair<int, int> > > PQ;
vector<pair<int, int> > Adj[N + 1];
int n, m, d[N + 1], res[N + 1], lab[N + 1], q;
set<int> dp[N + 1];
vector<int> id = {0};
int cnt[N + 1];
void read()
{
    cin >> n >> m;
    for (int i = 1; i <= m; ++ i)
    {
        int u, v, w;
        cin >> u >> v >> w;
        Adj[u].push_back({v, w});
        Adj[v].push_back({u, w});
    }
    memset(d, 0x3f, sizeof(d));
    memset(lab, -1, sizeof(lab));
    int k;
    cin >> k;
    for (int i = 1; i <= k; ++ i)
    {
        int u;
        cin >> u;
        d[u] = 0;
        PQ.push({0, u});
    }
    cin >> q;
    for (int i = 1; i <= q; ++ i)
    {
        int u, v;
        cin >> u >> v;
        dp[u].insert(i);
        dp[v].insert(i);
    }
}
int FindSet(int u)
{
    return lab[u] < 0 ? u : lab[u] = FindSet(lab[u]);
}
void Unite(int r, int s, int w)
{
    r = FindSet(r);
    s = FindSet(s);
    if (r == s)
    {
        return ;
    }
    if (lab[r] < lab[s])
    {
        swap(r, s);
    }
    lab[r] += lab[s];
    lab[s] = r;
    if (dp[r].size() < dp[s].size())
    {
        swap(dp[r], dp[s]);
    }
    for (int i : dp[s])
    {
        if (dp[r].find(i) != dp[r].end())
        {
            dp[r].erase(i);
            res[i] = w;
        }
        else
        {
            dp[r].insert(i);
        }
    }
}
void Dijkstra()
{
    while(!PQ.empty())
    {
        pair<int, int> p = PQ.top();
        PQ.pop();
        if (d[p.second] != p.first)
        {
            continue;
        }
        id.push_back(p.second);
        int u = p.second;
        for (auto p : Adj[u])
        {
            int v = p.first, w = p.second;
            if (d[v] > d[u] + w)
            {
                d[v] = d[u] + w;
                PQ.push({d[v], v});
            }
        }
    }
}
void solve()
{
    Dijkstra();
    for (int i = n; i >= 1; -- i)
    {
        int u = id[i];
        for (auto p : Adj[u])
        {
            int v = p.first;
            if (d[v] >= d[u])
            {
                Unite(u, v, d[u]);
            }
        }
    }
    for (int i = 1; i <= q; ++ i)
    {
        cout << res[i] << '\n';
    }
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    if (fopen(TASK".INP", "r"))
    {
        freopen(TASK".INP", "r", stdin);
        //freopen(TASK".OUT", "w", stdout);
    }
    int t = 1;
    bool typetest = false;
    if (typetest)
    {
        cin >> t;
    }
    for (int __ = 1; __ <= t; ++ __)
    {
        //cout << "Case " << __ << ": ";
        read();
        solve();
    }
}

Compilation message (stderr)

plan.cpp: In function 'int main()':
plan.cpp:128:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  128 |         freopen(TASK".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 13 / 13
• Subtask 3: 12 / 12
• Subtask 4: 19 / 19
• Subtask 5: 46 / 46