Submission #926463

#	Time	Username	Problem	Language	Result	Execution time	Memory
926463		vjudge1	Joker (BOI20_joker)	C++17	0 / 100	48 ms	125776 KiB

Joker

#include <bits/stdc++.h>

using namespace std;

#define all(a) a.begin(),a.end()
#define pb push_back
#define vt vector
#define endl '\n'
typedef long long ll;

const ll mod=1e9+7;
const ll inf=mod;
const int N=5e6+4;

string ans;
int n,m,q,u[N],v[N],used[N];
vt<int>g[N];

void dfs(int v,int val=1){
	used[v]=val;
//	cout<<v<<' '<<used[v]<<endl;
	for(int to:g[v]) {	
		if(!used[to]) dfs(to,3-val);
		if(used[to]==used[v]){
			ans="YES";
		}
	}
}

void solve(){
	cin>>n>>m>>q;
	for(int i=1; i<=m; ++i){
		cin>>u[i]>>v[i];
	}
	if(max({n,m,q})<=2000){
		while(q--){
			int l,r;
			cin>>l>>r;
			for(int i=1; i<l; ++i){
				g[u[i]].pb(v[i]);
				g[v[i]].pb(u[i]);
			}
			for(int i=r+1; i<=m; ++i){
				g[u[i]].pb(v[i]);
				g[v[i]].pb(u[i]);
			}
			ans="NO";
			for(int i=1; i<=n; ++i) if(!used[i]) dfs(i);
			cout<<ans<<endl;
			for(int i=1; i<l; ++i){
				g[u[i]].clear();
				g[v[i]].clear();
				used[u[i]]=0;
				used[v[i]]=0;
			}
			for(int i=r+1; i<=m; ++i){
				g[u[i]].clear();
				g[v[i]].clear();
				used[u[i]]=0;
				used[v[i]]=0;
			}
		}
	}
}

int main(){
	ios_base::sync_with_stdio(0);cin.tie(0);cout.tie(0);
	int tt=1;
//	cin>>tt;
	while(tt--) {
		solve();
	}
}

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