제출 #1256437

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1256437		BigBadBully	Stranded Far From Home (BOI22_island)	C++20	100 / 100	169 ms	31748 KiB

island

#include <bits/stdc++.h>
#define int long long
#define pii pair<int, int>
#define ff first
#define ss second
using namespace std;
const int inf = 1e18 + 5;
const int mod = 1e9 + 7;
const int maxm = 5e6 + 1;
const pii bad = {inf, inf};
using ll = long long;
using ld = long double;

void solve()
{
    int n, m;
    cin >> n >> m;
    vector<int> v(n);
    for (int i = 0; i < n; i++)
        cin >> v[i];

    vector<vector<pii>> adj(n);
    for (int i = 0; i < m; i++)
    {
        int a, b;
        cin >> a >> b;
        adj[--a].push_back({v[--b], b});
        adj[b].push_back({v[a], a});
    }

    for(auto&a:adj)
        sort(a.begin(),a.end()),reverse(a.begin(),a.end());

    vector<pii> orig(n);
    for (int i = 0; i < n; i++)
        orig[i] = {v[i], i};
    sort(orig.begin(), orig.end());
    vector<int> par(n, 0);
    for (int i = 0; i < n; i++)
        par[i] = i;
    auto sz = v;
    function<int(int)> fnd = [&](int x) -> int
    {
        if (par[x] == x)
            return x;
        return par[x] = fnd(par[x]);
    };
    vector<int> maxi = v;
    vector<int> af(n, -1);
    auto unite = [&](int a, int b)
    {
        a = fnd(a), b = fnd(b);
        if(a==b)return;
        if (maxi[a]>maxi[b])swap(a,b);
        if(maxi[a]!=maxi[b] && sz[a] >= maxi[b])
            af[a] = b;
        par[a] = b;
        maxi[b] = max(maxi[b],maxi[a]);
        sz[b] += sz[a];
    };
    
    
    orig.push_back({inf, inf});
    int l = 0;
    for (int r = 1; r <= n; r++)
    {
        if (orig[r].ff != orig[r - 1].ff)
        {
            for (int i = l; i < r; i++)
            {
                int idx = orig[i].ss;
                while(adj[idx].size() && (adj[idx].back()).ff <= orig[i].ff)
                    unite(adj[idx].back().ss,idx),adj[idx].pop_back();
            }   
            for (int i = l; i < r; i++)
                af[orig[i].ss] = fnd(orig[i].ss);
            
            l = r;
        }
    }
    int big = *max_element(v.begin(),v.end());
    fnd = [&](int x)->int
    {
        if(af[x]==-1)return -1;
        if (af[x]==x)
        {
            if (v[x] != big)
                return af[x] = -1;
            return x;
        }
            
          
        
        return af[x] = fnd(af[x]);
    };
    for (int i = 0; i < n; i++)
    {
        if (fnd(i)>=0)
            cout << '1';
        else
            cout << '0';
    }
    cout << '\n';
}


signed main()
{

    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    solve();
}

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