bzoj2049 [ SDOI2008 ] -- LCT

 1 #include<iostream>
 2 #include<cstdio>
 3 #include<cstring>
 4 using namespace std;
 5 #define N 10010
 6 int i,j,k,x,y,n,m,f[N],ch[N][2];
 7 bool r[N],b[N];
 8 char c[30];
 9 inline void Update(int x){
10     if(x==0)return;
11     swap(ch[x][0],ch[x][1]);
12     r[x]^=1;
13 }
14 inline void Pushdown(int x){
15     if(r[x]){
16         Update(ch[x][0]);
17         Update(ch[x][1]);
18         r[x]=0;
19     }
20 }
21 inline int Get(int x){return ch[f[x]][1]==x;}
22 inline void Rotate(int x){
23     bool d=Get(x);int y=f[x];
24     if(b[y])b[x]=1,b[y]=0;else ch[f[y]][Get(y)]=x;
25     ch[y][d]=ch[x][d^1];f[ch[y][d]]=y;
26     f[x]=f[y];ch[x][d^1]=y;f[y]=x;
27 }
28 inline void P(int x){
29     if(!b[x])P(f[x]);
30     Pushdown(x);
31 }
32 inline void Splay(int x){
33     P(x);
34     for(;!b[x];Rotate(x))
35     if(!b[f[x]])Rotate(Get(x)==Get(f[x])?f[x]:x);
36 }
37 inline void Access(int x){
38     int y=0;
39     while(x){
40         Splay(x);
41         b[ch[x][1]]=1;ch[x][1]=y;b[y]=0;
42         y=x;x=f[x];
43     }
44 }
45 inline void mr(int x){Access(x);Splay(x);Update(x);}
46 inline int Find(int x){
47     while(f[x])x=f[x];
48     return x;
49 }
50 inline void Link(int x,int y){
51     if(Find(x)==Find(y))return;
52     mr(x);f[x]=y;
53 }
54 inline void Cut(int x,int y){
55     mr(x);Access(y);Splay(y);
56     f[ch[y][0]]=0;b[ch[y][0]]=1;ch[y][0]=0;
57 }
58 int main()
59 {
60     scanf("%d%d",&n,&m);
61     for(i=1;i<=n;i++)b[i]=1;
62     while(m--){
63         scanf("%s%d%d",c,&x,&y);
64         if(c[0]=='C')Link(x,y);else
65         if(c[0]=='Q')if(Find(x)==Find(y))puts("Yes");else puts("No");else Cut(x,y);
66     }
67     return 0;
68 }