Submission #604825

#	Time	Username	Problem	Language	Result	Execution time	Memory
604825		errorgorn	Stranded Far From Home (BOI22_island)	C++17	100 / 100	510 ms	71232 KiB

island

#include <bits/stdc++.h>
using namespace std;

#define int long long
#define ii pair<int,int>
#define iii tuple<int,int,int>
#define fi first
#define se second
#define endl '\n'

#define puf push_front
#define pub push_back
#define pof pop_front
#define pob pop_back
#define lb lower_bound
#define ub upper_bound

#define rep(x,s,e) for (int x=(s)-((s)>(e));x!=(e)-((s)>(e));((s)<(e))?x++:x--)
#define all(x) (x).begin(),(x).end()
#define sz(x) (int) (x).size()

mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());

struct UFDS{
	int p[200005];
	
	UFDS(){
		rep(x,0,200005) p[x]=x;
	}
	
	int par(int i){
		if (p[i]==i) return i;
		else return p[i]=par(p[i]);
	}
} ufds;

int n,m;
int arr[200005];
vector<iii> edges;
set<int> s[200005];

signed main(){
	cin.tie(0);
	cout.tie(0);
	cin.sync_with_stdio(false);
	
	cin>>n>>m;
	rep(x,1,n+1) cin>>arr[x];
	
	int a,b;
	rep(x,0,m){
		cin>>a>>b;
		if (arr[a]<arr[b]) swap(a,b);
		edges.pub({arr[a],a,b});
	}
	
	sort(all(edges));
	rep(x,1,n+1) s[x].insert(x);
	
	for (auto [w,a,b]:edges){
		a=ufds.par(a),b=ufds.par(b);
		if (a==b) continue;
		
		if (arr[b]>=w){
			if (sz(s[a])<sz(s[b])) swap(s[a],s[b]);
			for (auto it:s[b]) s[a].insert(it);
		}
		arr[a]+=arr[b];
		ufds.p[b]=a;
	}
	
	int idx=ufds.par(1);
	
	string ans(n,'0');
	for (auto it:s[idx]) ans[it-1]='1';
	
	cout<<ans<<endl;
}

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