Submission #583944

#	Time	Username	Problem	Language	Result	Execution time	Memory
583944		cheissmart	Stranded Far From Home (BOI22_island)	C++14	100 / 100	478 ms	50820 KiB

island

#include <bits/stdc++.h>
#define IO_OP ios::sync_with_stdio(0), cin.tie(0)
#define F first
#define S second
#define V vector
#define PB push_back
#define EB emplace_back
#define MP make_pair
#define SZ(v) int((v).size())
#define ALL(v) (v).begin(), (v).end()

using namespace std;

typedef long long ll;
typedef pair<int, int> pi;
typedef V<int> vi;

const int INF = 1e9 + 7, N = 2e5 + 7;

int s[N], where[N], ans[N], pos[N];
ll sum[N];
vi who[N], alive[N];
vi G[N];

signed main()
{
	IO_OP;

	int n, m;
	cin >> n >> m;
	for(int i = 1; i <= n; i++)
		cin >> s[i];

	vi p(n);
	iota(ALL(p), 1);
	sort(ALL(p), [&] (int a, int b) {
		return s[a] < s[b];
	});
	for(int i = 0; i < n; i++)
		pos[p[i]] = i;

	for(int i = 0; i < m; i++) {
		int u, v;
		cin >> u >> v;
		G[u].PB(v);
		G[v].PB(u);
	}

	auto unite = [&] (int x, int y) {
		if(SZ(who[x]) > SZ(who[y])) swap(x, y);
		for(int u:who[x]) {
			who[y].PB(u);
			where[u] = y;
		}
		sum[y] += sum[x];
		if(SZ(alive[x]) > SZ(alive[y]))
			swap(alive[x], alive[y]);
		for(int u:alive[x])
			alive[y].PB(u);
	};

	for(int u:p) {
		ans[u] = 1;
		where[u] = u, who[u].PB(u), alive[u].PB(u), sum[u] = s[u];

		vi cc;
		for(int v:G[u]) if(pos[v] < pos[u])
			cc.PB(where[v]);
		sort(ALL(cc));
		cc.resize(unique(ALL(cc)) - cc.begin());

		for(int c:cc) if(sum[c] < s[u]) {
			for(int v:alive[c])
				ans[v] = 0;
			alive[c].clear();
		}

		for(int c:cc)
			unite(where[u], c);
	}

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

}

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