### [國家集訓隊]Tree II

``````#include<algorithm>
#include<iostream>
#include<cstring>
#include<cstdio>
#define maxn 300005
#define re register
#define LL long long
#define max(a,b) ((a)>(b)?(a):(b))
#define min(a,b) ((a)<(b)?(a):(b))
{
char c=getchar();int x=0;while(c<'0'||c>'9') c=getchar();
while(c>='0'&&c<='9') x=(x<<3)+(x<<1)+c-48,c=getchar();return x;
}
int n,m;
int fa[maxn],v[maxn],s[maxn],ch[maxn][2],st[maxn],rev[maxn];
inline int nroot(int x) {return ch[fa[x]][0]==x||ch[fa[x]][1]==x;}
inline void pushup(int x) {s[x]=s[ch[x][0]]^s[ch[x][1]]^v[x];}
inline void pushdown(int x) {
if(!rev[x]) return;
rev[x]=0,rev[ch[x][0]]^=1,rev[ch[x][1]]^=1;
std::swap(ch[ch[x][0]][0],ch[ch[x][0]][1]);
std::swap(ch[ch[x][1]][0],ch[ch[x][1]][1]);
}
inline void rotate(int x) {
int y=fa[x],z=fa[y],k=ch[y][1]==x,w=ch[x][k^1];
if(nroot(y)) ch[z][ch[z][1]==y]=x;
ch[x][k^1]=y,ch[y][k]=w;
pushup(y),pushup(x);fa[w]=y;fa[y]=x,fa[x]=z;
}
inline void splay(int x) {
int y=x,top=0;
st[++top]=x;
while(nroot(y)) st[++top]=fa[y],y=fa[y];
while(top) pushdown(st[top--]);
while(nroot(x)) {
int y=fa[x];
if(nroot(y)) rotate((ch[y][1]==x)^(ch[fa[y]][1]==y)?x:y);
rotate(x);
}
}
inline void access(int x) {
for(re int y=0;x;y=x,x=fa[x])
splay(x),ch[x][1]=y,pushup(x);
}
inline void makeroot(int x) {
access(x);splay(x);rev[x]^=1;std::swap(ch[x][0],ch[x][1]);
}
inline int findroot(int x) {
access(x);splay(x);
while(ch[x][0]) pushdown(x),x=ch[x][0];
splay(x);return x;
}
inline void split(int x,int y) {
makeroot(x);access(y);splay(y);
}
inline void link(int x,int y) {
makeroot(x);
if(findroot(y)!=x)fa[x]=y;
}
inline void cut(int x,int y) {
makeroot(x);
if(findroot(y)==x&&fa[y]==x&&!ch[y][0]) ch[x][0]=fa[y]=0,pushup(x);
}
int main() {
int opt,x,y;
while(m--) {
if(opt==0) split(x,y),printf("%d\n",s[y]);
if(opt==2) cut(x,y);
if(opt==3) splay(x),v[x]=y,pushup(x);
}
return 0;
}``````