제출 #642286

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
642286		dozer	Joker (BOI20_joker)	C++14	6 / 100	182 ms	262144 KiB

Joker

#include <bits/stdc++.h>
using namespace std;
#define fileio() freopen("input.txt", "r", stdin), freopen("output.txt", "w", stdout)
#define fastio() cin.tie(0), ios_base::sync_with_stdio(0)
#define sp " "
#define endl "\n"
#define pb push_back
#define pii pair<int, int>
#define st first
#define nd second
#define N 200005

const int modulo = 1e9 + 7;
int ans[N], u[N], v[N], l[N], r[N];
vector<int> ind[N], root, gh[N];
map<int, int> res[N];

int find(vector<int> &b, int node)
{
	if (node < 0) return -(find(b, -node));
	if (node == b[node]) return node;
	return b[node] = find(b, b[node]);
}


int32_t main()
{
	fastio();


	int n, m, q;
	cin>>n>>m>>q;
	root.resize(n + 5, 0);
	for (int i = 1; i <= n; i++)
		root[i] = i;

	for (int i = 1; i <= m; i++)
	{
		cin>>u[i]>>v[i];
	}

	for (int i = 1; i <= q; i++)
	{
		cin>>l[i]>>r[i];
		ind[r[i]].pb(l[i]);
	}

	for (int i = m; i >= 1; i--)
	{
		sort(ind[i].begin(), ind[i].end());
		if (ind[i].size() > 0)
		{
			vector<int> tmp(root.begin(), root.end());
			gh[i] = tmp;

		}
		if (ans[i] == 1) 
		{
			ans[i - 1] = 1;
			continue;
		}
		int a = find(root, u[i]), b = find(root, v[i]);
		if (a == b) ans[i - 1] = 1;
		else if (a < 0) a *= -1, b *= -1;
		root[a] = -b;
		//cout<<i<<sp<<ans[i]<<endl;
	}

	for (int i = m; i >= 1; i--)
	{
		if (ind[i].empty()) continue;
		int last = 1;
		for (auto j : ind[i])
		{
			if (ans[i] == 1 || res[i][last] == 1) 
			{
				res[i][j] = 1;
				//cout<<i<<sp<<j<<sp<<ans[i]<<sp<<res[i][j]<<endl;
				continue;
			}
			for (int k = last; k < j && res[i][j] == 0; k++)
			{
				int a = find(gh[i], u[k]), b = find(gh[i], v[k]);
				if (a == b) res[i][j] = 1;
				else if (a < 0) a *= -1, b *= -1;
				gh[i][a] = -b;
			}
			//cout<<i<<sp<<j<<sp<<res[i][j]<<endl;
			last = j;
		}
	}

	for (int i = 1; i <= q; i++)
	{
		if (res[r[i]][l[i]]) cout<<"YES\n";
		else cout<<"NO\n";
	}
	cerr<<"time taken : "<<(float)clock() / CLOCKS_PER_SEC<<" seconds\n";
}

• Subtask 1: 6 / 6
• Subtask 2: 0 / 8
• Subtask 3: 0 / 25
• Subtask 4: 0 / 10
• Subtask 5: 0 / 22
• Subtask 6: 0 / 29