Submission #1002485

#	Time	Username	Problem	Language	Result	Execution time	Memory
1002485		Andrey	Stranded Far From Home (BOI22_island)	C++14	100 / 100	144 ms	45040 KiB

island

#include<bits/stdc++.h>
using namespace std;
 
vector<long long> haha[200001];
vector<long long> dsu(200001);
vector<long long> tree[200001];
vector<long long> st(200001);
vector<long long> wow(200001);
vector<bool> ans(200001);
 
long long calc(long long a) {
    long long c = a,e = a;
    while(dsu[c] != c) {
        c = dsu[c];
    }
    while(e != dsu[e]) {
        long long d = dsu[e];
        dsu[e] = c;
        e = d;
    }
    return c;
}
 
void dfs(long long a) {
    st[a] = wow[a];
    for(long long v: tree[a]) {
        dfs(v);
        st[a]+=st[v];
    }
}
 
void dude(long long a) {
    ans[a] = true;
    for(long long v: tree[a]) {
        if(st[v] >= wow[a]) {
            dude(v);
        }
    }
}
 
int main()
{
    ios_base::sync_with_stdio(NULL);
    cin.tie(NULL);
    cout.tie(NULL);
    long long n,m,a,b;
    cin >> n >> m;
    vector<pair<long long,long long>> wut(0);
    for(long long i = 1; i <= n; i++) {
        cin >> wow[i];
        dsu[i] = i;
        wut.push_back({wow[i],i});
    }
    sort(wut.begin(),wut.end());
    vector<int> pos(n+1);
    for(int i = 0; i < n; i++) {
        pos[wut[i].second] = i;
    }
    for(long long i = 0; i < m; i++) {
        cin >> a >> b;
        if(pos[a] > pos[b]) {
            haha[a].push_back(b);
        }
        else {
            haha[b].push_back(a);
        }
    }
    for(long long i = 0; i < wut.size(); i++) {
        long long a = wut[i].second;
        for(long long v: haha[a]) {
            if(calc(v) != calc(a)) {
                tree[a].push_back(calc(v));
                dsu[calc(v)] = a;
            }
        }
    }
    dfs(wut[n-1].second);
    dude(wut[n-1].second);
    for(long long i = 1; i <= n; i++) {
        cout << ans[i];
    }
    cout << endl;
    return 0;
}

Compilation message (stderr)

island.cpp: In function 'int main()':
island.cpp:68:28: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   68 |     for(long long i = 0; i < wut.size(); i++) {
      |                          ~~^~~~~~~~~~~~

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