제출 #906092

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
906092		sunwukong123	Joker (BOI20_joker)	C++14	0 / 100	2040 ms	44992 KiB

Joker

#include <bits/stdc++.h>
using namespace std;
#define int long long 
#ifdef LOCAL
void debug_out() {cerr<<endl;}
template <typename Head, typename... Tail>
void debug_out(Head _H, Tail... _T) {cerr<<" "<<to_string(_H);debug_out(_T...);}
#define debug(...) cerr<<"["<<#__VA_ARGS__<<"]:",debug_out(__VA_ARGS__)
#else
#define debug(...)
#endif
const int MAXN = 200005;
const int inf=1000000500ll;
const long long oo =1000000000000000500ll;
const int MOD = (int)1e9 + 7;
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
typedef pair<int,int> pi; 
int n,m,q;
pi A[MAXN];
struct ufds_{
	int p[MAXN],dist[MAXN];
	vector<array<int,4>>rollback;
	int TIME=0;
	bool nonbi=0;
	ufds_(){
		iota(p,p+MAXN,0);
	}
	
	pi find(int x){
		if(x==p[x])return {x,dist[x]};
		else{
			rollback.push_back({TIME,x,p[x],dist[x]});
			int cur=dist[x];
			pi np=find(p[x]);
			dist[x]^=np.second;
			p[x]=np.first;
			return {p[x],dist[x]};
		}
	}
	void merge(int x, int y){
		++TIME;
		debug(TIME);
		int distx=dist[x];
		int disty=dist[y];
		if(find(x) == find(y)){
			debug(dist[x],p[x],dist[y],p[y]);
			if((dist[x] ^ dist[y]) == 0){
				rollback.push_back({TIME,-1,nonbi,nonbi});
				nonbi=1;
			} else {
				
			}
			return;
		}
		
		x=find(x).first;
		rollback.push_back({TIME,x,p[x],dist[x]});
		dist[x]=distx^disty^1;
		p[x]=find(y).first;
		
	}
	void rb(int dt){
		int tt=TIME-dt;
		while(rollback.size() && rollback.back()[0]>tt){

			array<int,4>cur=rollback.back();rollback.pop_back();
			if(cur[1] == -1){
				nonbi=cur[2];
			} else{
				p[cur[1]]=cur[2];
				dist[cur[1]]=cur[3];
			}
			
		}
		TIME-=dt;
	}
}ufds;
int ans[MAXN];
void dnc(int s, int e, int l, int r){
	if(s>e)return;
	int m=(s+e)/2;
	for(int i=s;i<=m;i++){
		ufds.merge(A[i].first,A[i].second);
	}
	
	if(m==6){
		for(int i=1;i<=n;i++){
			debug(i,ufds.p[i],ufds.dist[i]);
		}
		//exit(0);
	}
	
	for(int i=r;i>=l;i--){

		ufds.merge(A[i].first,A[i].second);
		if(ufds.nonbi){
			ans[m]=i;
			break;
		}
	}
	
	//if(m==6)exit(0);
	ufds.rb(r-ans[m]+1);
	if(s!=e){
		dnc(m+1,e,ans[m],r);
	}
	
	ufds.rb(m-s+1);
	if(s!=e){
		for(int i=r;i>=ans[m];i--){
			ufds.merge(A[i].first,A[i].second);
		}
		dnc(s,m-1,l,ans[m]);
		ufds.rb(r-ans[m]+1);
	}
	
}

int32_t main() 
{
	ios_base::sync_with_stdio(0); cin.tie(0);
	cin>>n>>m>>q;
	//check if whole graph is bipartite
	for(int i=1;i<=m;i++)cin>>A[i].first>>A[i].second;
	dnc(1,m,1,m);
	for(int i=1;i<=m;i++){
		debug(i,ans[i]);
	}
	while(q--){
		int l,r;cin>>l>>r;
		if(ans[l]>r)cout<<"YES\n";
		else cout<<"NO\n";
	}
}	

컴파일 시 표준 에러 (stderr) 메시지

Joker.cpp: In member function 'pi ufds_::find(long long int)':
Joker.cpp:33:8: warning: unused variable 'cur' [-Wunused-variable]
   33 |    int cur=dist[x];
      |        ^~~

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