Submission #654570

#	Time	Username	Problem	Language	Result	Execution time	Memory
654570		erto	Stranded Far From Home (BOI22_island)	C++17	100 / 100	742 ms	141488 KiB

island

#include <bits/stdc++.h>
typedef long long int ll;
typedef long double ld;
#define INF (int)(1e9 + 7)
#define INF2 998244353
#define N (ll)(2e5 + 5)
//#define f first
//#define s second
#define int ll
#define lsb(x) (x & (-x))
using namespace std;

int n, m, g, h;
int ans[N];
set<pair<int, int>> v[N];
int a[N];
int p[N], sz[N];
bool used[N];

set<int> ss[N];

int get(int x){
    return p[x] = (p[x] == x ? x : get(p[x]));
}

void unite(int x, int y){
    int a = get(x), b = get(y);
    if(a == b)return;
    if(ss[a].size() < ss[b].size())swap(ss[a], ss[b]);
    sz[a] += sz[b];
    p[b] = a;

    for(auto u : ss[b]){
        ss[a].insert(u);
    }
}

void solve(){
    cin >> n >> m;

    int maxx=0;

    for(int i=1; i<=n; i++){
        cin >> a[i];
        if(maxx < a[i]){
            maxx = a[i];
        }
    }

    for(int i=1; i<=m; i++){
        cin >> g >> h;
        v[g].insert({a[h], h});
        v[h].insert({a[g], g});
    }

    priority_queue<pair<int, int>> pq;
    for(int i=1; i<=n; i++){
        pq.push({-a[i], i});
    }

    for(int i=1; i<=n; i++){
        ans[i] = 1;
        sz[i] = a[i];
        p[i] = i;
        ss[i].insert(i);
    }

    while(!pq.empty()){
        auto p = pq.top();
        pq.pop();
        int i = p.second;
        used[i] = 1;
        //cout << i << ' ';

        for(auto z : v[i]){
            int u = z.second;
            //if(i == 4)cout << u << a[u] << sz[get(i)] << '\n';
            
            if(a[i] >= a[u]){
                if(sz[get(u)] < a[i]){
                    //cout << i << u << '\n';
                    vector<int> v2;
                    for(int r : ss[get(u)]){
                        if(used[r])v2.push_back(r);
                    }
                    for(int r : v2){
                        ans[r] = 0;
                        //ss[get(u)].erase(r);
                    }
                }
                unite(i, u);
            }
        }
    }

    //for(int u : ss[get(maxnode)])ans[u] = 1;


    for(int i=1; i<=n; i++){
        cout << ans[i];
    }
}   


signed main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int T = 1;
    //cin>>T;
    for(int i=1; i<=T; i++){
        solve();
    }
}

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