Submission #603926

#	Time	Username	Problem	Language	Result	Execution time	Memory
603926		MohamedAhmed04	Stranded Far From Home (BOI22_island)	C++14	100 / 100	282 ms	38464 KiB

island

#include <bits/stdc++.h>

using namespace std ;

const int MAX = 2e5 + 10 ;

int arr[MAX] ;
int n , m ;

vector< vector<int> >adj(MAX) ;

int par[MAX] , sz[MAX] ;
long long val[MAX] ;
vector<int>v[MAX] ;

void init()
{
	for(int i = 1 ; i <= n ; ++i)
		par[i] = i , sz[i] = 1 , val[i] = arr[i] , v[i].push_back(i) ;
}

int root(int node)
{
	if(par[node] == node)
		return node ;
	return (par[node] = root(par[node])) ;
}

void Union(int x , int y)
{
	int a = root(x) ;
	int b = root(y) ;
	if(sz[a] < sz[b])
		swap(a , b) ;
	while(v[b].size())
		v[a].push_back(v[b].back()) , v[b].pop_back() ;
	par[b] = a ;
	sz[a] += sz[b] ;
	val[a] += val[b] ;
}

int mark[MAX] , ans[MAX] ;

int main()
{
	ios_base::sync_with_stdio(0) ;
	cin.tie(0) ;
	cin>>n>>m ;
	for(int i = 1 ; i <= n ; ++i)
		cin>>arr[i] ;
	for(int i = 0 ; i < m ; ++i)
	{
		int x , y ;
		cin>>x>>y ;
		adj[x].push_back(y) ;
		adj[y].push_back(x) ;
	}
	vector< pair<int , int> >vp ;
	for(int i = 1 ; i <= n ; ++i)
		vp.emplace_back(arr[i] , i) ;
	sort(vp.begin() , vp.end()) ;
	init() ;
	for(auto &p : vp)
	{
		int node = p.second ;
		for(auto &child : adj[node])
		{
			if((!mark[child]) || root(node) == root(child))
				continue ;
			int r = root(child) ;
			if(val[r] < arr[node])
				v[r].clear() ;
			Union(node , child) ;
		}
		mark[node] = 1 ;
	}
	for(auto &node : v[root(1)])
		ans[node] = 1 ;
	for(int i = 1 ; i <= n ; ++i)
		cout<<ans[i] ;
	cout<<"\n" ;
	return 0 ;
}

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