http://www.lydsy.com/JudgeOnline/problem.php?id=3282
大概又是一道lct的裸题
#include<cstdio> #include<algorithm> const int maxn = 320007; inline int read() { int x=0,f=1;char c=getchar(); while(c<‘0‘||c>‘9‘) { if(c==‘-‘)f=-1;c=getchar(); } while(c<=‘9‘&&c>=‘0‘) { x=x*10+c-‘0‘,c=getchar(); } return x*f; } #define lc ch[x][0] #define rc ch[x][1] bool rev[maxn]; int stack[maxn],top; int ans[maxn],v[maxn]; int fa[maxn],ch[maxn][2]; bool isroot(int x) { return ch[fa[x]][1]!=x&&ch[fa[x]][0]!=x; } void update(int x){ ans[x]=ans[lc]^ans[rc]^v[x]; } void pushdown(int x) { if(rev[x]) { rev[x]=0;rev[lc]^=1;rev[rc]^=1; std::swap(lc,rc); } return; } void rotate(int x) { int y=fa[x],z=fa[y],d=(ch[y][1]==x)^1; if(!isroot(y)) ch[z][ch[z][1]==y]=x; fa[x]=z; ch[y][d^1]=ch[x][d],fa[ch[x][d]]=y; ch[x][d]=y;fa[y]=x; return update(y),update(x); } void splay(int x) { stack[++top]=x; for(int i=x;!isroot(i);i=fa[i]) stack[++top]=fa[i]; while(top)pushdown(stack[top--]); while(!isroot(x)) { int y=fa[x],z=fa[y]; if(!isroot(y)) { if(ch[y][1]==x^ch[z][1]==y)rotate(x); else rotate(y); } rotate(x); } return ; } void access(int x) { for(int i=0;x;i=x,x=fa[x]) { splay(x),ch[x][1]=i,update(x); } return ; } void makeroot(int x) { access(x);splay(x);rev[x]^=1; return; } void split(int x,int y) { makeroot(x),access(y);return splay(y); } void cut(int x,int y) { split(x,y); ch[y][0]=fa[ch[y][0]]=0; return; } void link(int x,int y) { makeroot(x),fa[x]=y;return splay(x); } int find(int x) { for(access(x),splay(x);ch[x][0];x=ch[x][0]); return x; } int query(int x,int y) { split(x,y); return ans[y]; } void modify(int x,int w) { access(x),splay(x),v[x]=w; return update(x); } int main() { int n,m; n=read(),m=read(); for(int i=1;i<=n;++i) { v[i]=read();ans[i]=v[i]; } for(int op,x,y,i=1;i<=m;++i) { op=read(),x=read(),y=read(); if(!op) printf("%d\n",query(x,y)); else if(op==1) { if(find(x)!=find(y)) link(x,y); } else if(op==2) { if(find(x)==find(y))cut(x,y); } else modify(x,y); } return 0; }