Submission #666339

#	Time	Username	Problem	Language	Result	Execution time	Memory
666339		mychecksedad	Stranded Far From Home (BOI22_island)	C++17	10 / 100	215 ms	30336 KiB

island

/* Author : Mychecksdead */
#include<bits/stdc++.h>
using namespace std;
#define all(x) x.begin(), x.end()
#define pb push_back
const int N = 2e5 + 100;

struct Dsu{
    vector<int> s, p;
    vector<long long> sum;
    Dsu(int n, int a[]){
        s.resize(n + 1, 1);
        p.resize(n + 1);
        sum.resize(n + 1, 0ll);
        for(int i = 0; i <= n; ++i) p[i] = i;
        for(int i = 0; i <= n; ++i) sum[i] = a[i];
    }
    int find(int v){
        if(v==p[v]) return v;
        return (p[v]=find(p[v]));
    }
    void merge(int a, int b){
        a = find(a);
        b = find(b);
        if(a != b){
            if(s[a] > s[b]) swap(a, b);
            p[a] = b;
            s[b] += s[a];
            sum[b] += sum[a];
        }
    }
};


int n, m, a[N];
vector<int> g[N], M[N];
vector<bool> vis, ans;
pair<int, int> b[N];
int main(){
    cin.tie(0); ios::sync_with_stdio(0);
    cin >> n >> m;
    for(int i = 1; i <= n; ++i) cin >> a[i];
    for(int i = 1; i <= n; ++i) b[i] = {a[i], i};
    for(int i = 0; i < m; ++i){
        int a, b; cin >> a >> b;
        g[a].pb(b);
        g[b].pb(a);
    }


    Dsu d(n, a);
    sort(b + 1, b + 1 + n);
    ans.resize(n + 1, 0);
    vis.resize(n + 1, 0);

    for(int i = 1; i <= n; ++i){
        int v = b[i].second;
        for(int u: g[v]){
            if(vis[u]){
                int co = d.find(u);
                if(d.sum[co] >= a[v]){
                    M[v].pb(u);
                    M[u].pb(v);
                }
            }
        }
        for(int u: g[v]){
            if(vis[u]){
                d.merge(u, v);
            }
        }
        vis[v] = 1;
    }   
    vis.clear();
    vis.resize(n+1, 0);
    queue<int> q;
    vis[b[n].second] = ans[b[n].second] = 1;
    q.push(b[n].second);
    while(!q.empty()){
        int v = q.front(); q.pop();
        ans[v] = 1;
        for(int u: M[v]){
            if(!vis[u]){
                vis[u] = 1;
                q.push(u);
            }
        }
    }

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

    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 15
• Subtask 4: 0 / 30
• Subtask 5: 0 / 35