[Sdoi2008]Cave 洞穴勘测

BZOJ好了以后去交了这题，算是动态树补完

题目大意：

求一棵树上任意两点的连通性

这道题算是真真正正的link-cut tree了，之前的动态树题目都没有涉及link和cut操作

所以这道题让我发现了我在写cut过程中的一个错误，也让我更加深刻的体会到了link-cut tree的优美

对于修改，link cut即可

对于每个询问，看他们是否在同一棵树中

code：

//Lib#include<cstdio>#include<cstring>#include<cstdlib>#include<cmath>#include<ctime>#include<iostream>#include<algorithm>#include<vector>#include<string>#include<queue>using namespace std;//Macro#define rep(i,a,b) for(int i=a,tt=b;i<=tt;++i)#define rrep(i,a,b) for(int i=a,tt=b;i>=tt;--i)#define erep(i,e,x) for(int i=x;i;i=e[i].next)#define irep(i,x) for(__typedef(x.begin()) i=x.begin();i!=x.end();i++)#define read() (strtol(ipos,&ipos,10))#define sqr(x) ((x)*(x))#define pb push_back#define PS system("pause");typedef long long ll;typedef pair<int,int> pii;const int oo=~0U>>1;const double inf=1e20;const double eps=1e-6;string name="",in=".in",out=".out";//Varstruct T{int LC,RC,FA;bool REV;#define lc(x) tree[x].LC#define rc(x) tree[x].RC#define fa(x) tree[x].FA#define rev(x) tree[x].REV}tree[10008];int n,m;void Update(int x){if(rev(x)){swap(lc(x),rc(x));rev(x)^=1;rev(lc(x))^=1;rev(rc(x))^=1;}}void Zig(int x){int y=fa(x),z=fa(y);if(lc(z)==y)lc(z)=x;else if(rc(z)==y)rc(z)=x;fa(x)=z;fa(rc(x))=y;lc(y)=rc(x);fa(y)=x;rc(x)=y;Update(y);}void Zag(int x){int y=fa(x),z=fa(y);if(lc(z)==y)lc(z)=x;else if(rc(z)==y)rc(z)=x;fa(x)=z;fa(lc(x))=y;rc(y)=lc(x);fa(y)=x;lc(x)=y;Update(y);}bool isRoot(int x){return lc(fa(x))!=x&&rc(fa(x))!=x;}void Push_Down(int x){if(!isRoot(x))Push_Down(fa(x));Update(x);}void Splay(int x){Push_Down(x);for(int y,z;!isRoot(x);){y=fa(x);z=fa(y);if(isRoot(y))if(lc(y)==x)Zig(x);else Zag(x);elseif(lc(z)==y)if(lc(y)==x)Zig(y),Zig(x);else Zag(x),Zig(x);elseif(rc(y)==x)Zag(y),Zag(x);else Zig(x),Zag(x);}Update(x);}void Expose(int x){for(int y=0;x;x=fa(x)){Splay(x);rc(x)=y;Update(x);y=x;}}void Evert(int x){Expose(x);Splay(x);rev(x)^=1;}void Link(int x,int y){Evert(x);fa(x)=y;}void Cut(int x,int y){Expose(y);Splay(x);if(fa(x)==y)fa(x)=0;else{Expose(x);Splay(y);fa(y)=0;}}bool Query(int a,int b){int x=a,y=b;Expose(y);for(y=0;x;x=fa(x)){Splay(x);if(!fa(x))break;y=x;}for(;rc(x);x=rc(x));return x==b;}void Work(){int a,b;char ch[10];rep(i,1,m){scanf("%s%d%d",ch,&a,&b);if(ch[0]=='C')Link(a,b);if(ch[0]=='D')Cut(a,b);if(ch[0]=='Q')puts(Query(a,b)?"Yes":"No");}}int main(){//freopen((name+in).c_str(),"r",stdin);//freopen((name+out).c_str(),"w",stdout);scanf("%d%d",&n,&m);Work();return 0;}