Submission #696866

#	Time	Username	Problem	Language	Result	Execution time	Memory
696866		Tien_Noob	Stranded Far From Home (BOI22_island)	C++17	100 / 100	215 ms	35460 KiB

island

//Make CSP great again
//Vengeance
#include <bits/stdc++.h>
#define TASK "TESTCODE"
using namespace std;
const int N = 2e5;
int lab[N + 1];
vector<int> f[N + 1], adj[N + 1];
long long sum[N + 1];
int n, m, id[N + 1], s[N + 1];
bool res[N + 1];
int FindSet(int u)
{
    return lab[u] < 0 ? u : lab[u] = FindSet(lab[u]);
}
void unite(int u, int v)
{
    u = FindSet(u);
    v = FindSet(v);
    if (u == v)
    {
        return ;
    }
    if (lab[u] > lab[v])
    {
        swap(u, v);
    }
    lab[u] += lab[v];
    sum[u] += sum[v];
    lab[v] = u;
    move(f[v].begin(), f[v].end(), back_inserter(f[u]));
}
void read()
{
    cin >> n >> m;
    for (int i = 1; i <= n; ++ i)
    {
        cin >> s[i];
        sum[i] = s[i];
        lab[i] = -1;
        f[i] = {i};
        id[i] = i;
    }
    while(m--)
    {
        int u, v;
        cin >> u >> v;
        adj[u].push_back(v);
        adj[v].push_back(u);
    }
}
void solve()
{
    sort(id + 1, id + n + 1, [&](const int x, const int &y)
         {
             return s[x] < s[y];
         });
    for (int i = 1; i <= n; ++ i)
    {
        int u = id[i];
        for (int v : adj[u])
        {
            if (s[v] <= s[u])
            {
                if (sum[FindSet(v)] < s[u])
                {
                    f[FindSet(v)].clear();
                }
                unite(u, v);
            }
        }
    }
    int root = FindSet(id[n]);
    for (int u : f[root])
    {
        res[u] = true;
    }
    for (int u = 1; u <= n; ++ u)
    {
        cout << res[u];
    }
}
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)

island.cpp: In function 'int main()':
island.cpp:89:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   89 |         freopen(TASK".INP", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 15 / 15
• Subtask 4: 30 / 30
• Subtask 5: 35 / 35