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IDProblemSubmitterResultTimeMemoryLanguageFile sizeSubmit timeJudge time
#20536#2214. Link Cut Digraph2018ty22#WA 629ms11556kbC++202.0kb2022-02-16 14:51:302022-05-03 10:26:33

Judging History

你现在查看的是最新测评结果

  • [2023-08-10 23:21:45]
  • System Update: QOJ starts to keep a history of the judgings of all the submissions.
  • [2022-05-03 10:26:33]
  • 评测
  • 测评结果:WA
  • 用时:629ms
  • 内存:11556kb
  • [2022-02-16 14:51:30]
  • 提交

answer

#include<algorithm>
#include<cstdio>
#define ll long long
#define min(a,b) (a<b?a:b)
using namespace std;
struct node{
	int x,y,t;
}b[250001];
int n,m,fa[100001],siz[100001];
int head[100001],s[250001],nxt[250001];
int dfn[100001],lst[100001],tot;
int st[100001],top;
int p[250001],cp[250001];
bool vis[100001];
ll ans;
bool cmp(const node x,const node y){return x.t<y.t;}
inline int find(int x)
{
	if(fa[x]==x)return x;
	if(fa[x])return fa[x]=find(fa[x]);
	return x;
}
void tarjan(const int&x)
{
	dfn[x]=lst[x]=++tot;
	st[++top]=x;vis[x]=1;
	for(int i=head[x];i;i=nxt[i])
		if(!dfn[s[i]])
			tarjan(s[i]),lst[x]=min(lst[x],lst[s[i]]);
		else if(vis[s[i]])
			lst[x]=min(lst[x],lst[s[i]]);
	if(lst[x]==dfn[x])
	{
		while(st[top]!=x)
			fa[st[top]]=x,vis[st[top]]=0,--top;
		vis[x]=0,--top;
	}
}
void solve(const int&l,const int&r,const int&l1,const int&r1)
{
	if(l>=r||l1>r1)return;
	#define xx b[p[i]].x
	#define yy b[p[i]].y
	#define FoR for(int i=l1;i<=r1&&b[p[i]].t<=mid;++i)
	int mid=l+r>>1,num=0;tot=top=0;
	for(int i=l1;i<=r1;++i)
		fa[xx]=fa[yy]=0;
	FoR{
		vis[xx]=vis[yy]=0;
		head[xx]=head[yy]=0;
		dfn[xx]=dfn[yy]=0;
	}
	FoR{
		s[++num]=yy;
		nxt[num]=head[xx];
		head[xx]=num;
	}
	FoR if(!dfn[xx])tarjan(xx);
	int n1=l1-1,n2=0;
	for(int i=l1;i<=r1;++i)
		if(b[p[i]].t<=mid&&find(xx)==find(yy))
			p[++n1]=p[i];
		else
		{
			xx=find(xx);yy=find(yy);
			if(b[p[i]].t<=mid)b[p[i]].t=mid+1;
			cp[++n2]=p[i];
		}
	for(int i=1;i<=n2;++i)p[n1+i]=cp[i];
	solve(l,mid,l1,l1+n1-1);
	solve(mid+1,r,l1+n1,r1);
}
int main()
{
	scanf("%d%d",&n,&m);
	for(int i=1;i<=m;++i)
		scanf("%d%d",&b[i].x,&b[i].y),b[i].t=i,p[i]=i;
	solve(1,m+1,1,m);
	for(int i=1;i<=n;++i)fa[i]=0,siz[i]=1;
	sort(b+1,b+m+1,cmp);
	for(int i=1,j=1;i<=m;++i)
	{
		while(j<=m&&b[j].t<=i)
		{
			int x=find(b[j].x),y=find(b[j].y);
			if(x!=y)
			{
				ans+=(ll)(siz[x]+siz[y])*(siz[x]+siz[y]-1)-(ll)siz[x]*(siz[x]-1)-(ll)siz[y]*(siz[y]-1);
				siz[x]+=siz[y];fa[y]=x;
			}
			++j;
		}
		printf("%lld\n",ans>>1ll);
	}
}

Details

Test #1:

score: 0
Wrong Answer
time: 629ms
memory: 11556kb