#include<cstdio>
#include<algorithm>
int p,q,a,cyc,t,co[5],link[1000003][2],par[5][1000002],deg[5][1000002],cycsz,sz[1000002],rank[5][1000002];
bool overtwo,check[5];
int find(int num,int AA){if(AA==par[num][AA])return AA;else return par[num][AA]=find(num,par[num][AA]);}
void unite(int num,int AA,int BB)
{
AA=find(num,AA);BB=find(num,BB);
if(rank[num][AA]<rank[num][BB])par[num][AA]=BB;
else
{
if(rank[num][AA]==rank[num][BB])rank[num][AA]++;
par[num][BB]=AA;
}
}
void add(int r,int s)
{
for(int i=1;i<=4;i++)
{
if(check[i]==0)continue;
if(co[i]==r||co[i]==s)continue;
deg[i][r]++;deg[i][s]++;
if(deg[i][r]>=3||deg[i][s]>=3)check[i]=0;
int rr=find(i,r);ss=find(i,s);
if(rr==ss)check[i]=0;
else
{
unite(i,rr,ss);
}
}
}
void make(int r)
{
int u=1;
co[u++]=r;
for(int i=0;i<t;i++)
{
if(link[i][0]==r)co[u++]=link[i][1];
else if(link[i][1]==r)co[u++]=link[i][0];
}
for(int i=1;i<=4;i++)
{
check[i]=1;
for(int j=0;j<a;j++)par[i][j]=j,rank[i][j]=1;
}
for(int i=0;i<t;i++)add(link[i][0],link[i][1]);
}
void Init(int N)
{
a=N;
for(int i=0;i<N;i++)rank[0][i]=1,par[0][i]=i,sz[i]=1;
}
void Link(int A, int B)
{
p=A;q=B;
link[t][0]=p;link[t][1]=q;t++;
deg[0][p]++;deg[0][q]++;
if(deg[0][p]==3&&overtwo==0){
overtwo=1;
make(p);
}
else if(overtwo==0&°[0][q]==3)
{
overtwo=1;
make(q);
}
else if(overtwo==0)
{
p=find(0,p);q=find(0,q);
if(p==q){cyc++;cycsz=sz[p];}
else
{
unite(0,p,q);
sz[p]+=sz[q];
sz[q]=sz[p];
}
}
else
{
add(p,q);
}
}
int CountCritical()
{
if(cyc>1)return 0;
if(overtwo)
{
int ans=0;
for(int i=1;i<=4;i++)ans+=check[i];
return ans;
}
else
{
if(cyc)return cycsz;
else return a;
}
}
Compilation message
rings.cpp: In function 'void add(int, int)':
rings.cpp:25:26: error: 'ss' was not declared in this scope
int rr=find(i,r);ss=find(i,s);
^~
rings.cpp:25:26: note: suggested alternative: 's'
int rr=find(i,r);ss=find(i,s);
^~
s
