[BZOJ 3123]森林

这题和 COT1 一定有 JQ 喵~

线段树的启发式合并，每次要连接两个点时就对比较小的那棵树暴力 DFS 一边

然后均摊时间依旧是 logn 的，均摊真是世界上最邪恶的东西了……

然后这题的数据是要卖萌么？！
testcase 的存在意义是被阿卡林噎掉了么？！

 #include <cstdio>
 #include <cstring>
 #include <algorithm>
 const int sizeOfPoint=;
 const int sizeOfEdge=;
 const int sizeOfNode=;
 
 inline int lg(int);
 inline void swap(int & , int & );
 inline char getch();
 inline int getint();
 inline void putint(int);
 
 struct edge {int point; edge * next;};
 edge memory_edge[sizeOfEdge], * port_edge=memory_edge;
 inline edge * newedge(int, edge * );
 inline void link(int, int);
 
 struct node {int c; node * l , * r; inline node();};
 node * null=new node();
 node memory_node[sizeOfNode], * port_node=memory_node;
 inline node * newnode(node * =null);
 node * insert(node * , int, int, int);
 
 int b[sizeOfPoint], s[sizeOfPoint];
 int find(int);
 inline void merge(int, int);
 
 int testcase;
 int N, M, T, U;
 int p[sizeOfPoint], q[sizeOfPoint];
 int f[sizeOfPoint], d[sizeOfPoint], a[][sizeOfPoint];
 edge * e[sizeOfPoint];
 node * t[sizeOfPoint];
 inline void clear();
 inline bool cmp(int, int);
 inline void discretization();
 void dfs(int);
 inline int lca(int, int);
 inline int query(int, int, int);
 
 int main()
 {
     int lastans=;
 
     testcase=getint();
     for (testcase=;testcase;testcase--)
     {
         N=getint(), M=getint(), T=getint();
         clear();
         for (int i=;i<=N;i++)
             p[i]=getint();
         for (int i=;i<=M;i++)
         {
             int u=getint(), v=getint();
             link(u, v);
         }
         discretization();
 
         for (int i=;i<=N;i++) if (f[i]==-)
         {
             f[i]=; d[i]=;
             dfs(i);
         }
 
         for (int i=;i<=T;i++)
         {
             char c=getch(); int x=getint()^lastans, y=getint()^lastans;
             if (c=='Q')
             {
                 int k=getint()^lastans;
                 lastans=query(x, y, k);
                 putint(lastans);
             }
             else
             {
                 int bx=find(x), by=find(y);
                 if (bx==by) continue;
                 if (s[bx]<s[by]) swap(x, y);
                 link(x, y);
                 f[y]=x; d[y]=d[x]+;
                 dfs(y);
             }
         }
     }
 
     return ;
 }
 
 inline int lg(int x)
 {
     return -__builtin_clz(x);
 }
 inline void swap(int & x, int & y)
 {
     int z=x;
         x=y;
         y=z;
 }
 inline char getch()
 {
     register char ch;
     do ch=getchar(); while (ch!='L' && ch!='Q');
     return ch;
 }
 inline int getint()
 {
     register int num=;
     register char ch=, last;
     do last=ch, ch=getchar(); while (ch<'' || ch>'');
     do num=num*+ch-'', ch=getchar(); while (ch>='' && ch<='');
     if (last=='-') num=-num;
     return num;
 }
 inline void putint(int num)
 {
     char stack[];
     register int top=;
     if (num==) stack[top=]='';
     if (num<) putchar('-'), num=-num;
     for ( ;num;num/=) stack[++top]=num%+'';
     for ( ;top;top--) putchar(stack[top]);
     putchar('\n');
 }
 
 inline edge * newedge(int point, edge * next)
 {
     edge * ret=port_edge++;
     ret->point=point; ret->next=next;
     return ret;
 }
 inline void link(int u, int v)
 {
     e[u]=newedge(v, e[u]);
     e[v]=newedge(u, e[v]);
     merge(u, v);
 }
 
 inline node::node()
 {
     this->c=;
     this->l=this;
     this->r=this;
 }
 inline node * newnode(node * t)
 {
     node * newt=port_node++;
     *newt=*t;
     return newt;
 }
 node * insert(node * t, int l, int r, int k)
 {
     t=newnode(t);
     t->c++;
     if (l==r) return t;
 
     int m=(l+r)>>;
     if (k<=m) t->l=insert(t->l, l, m, k);
     else t->r=insert(t->r, m+, r, k);
     return t;
 }
 
 int find(int u)
 {
     return !b[u]?u:b[u]=find(b[u]);
 }
 inline void merge(int u, int v)
 {
     u=find(u); v=find(v);
     b[v]=u; s[u]+=s[v];
 }
 
 inline void clear()
 {
     port_edge=memory_edge;
     memset(e, , sizeof(e));
     port_node=memory_node;
     for (int i=;i<=N;i++) t[i]=null;
     memset(f, -, sizeof(f));
     memset(d, -, sizeof(d));
     memset(b, , sizeof(b));
     memset(a, , sizeof(a));
     for (int i=;i<=N;i++) s[i]=;
 }
 inline bool cmp(int a, int b)
 {
     return p[a]<p[b];
 }
 inline void discretization()
 {
     static int k[sizeOfPoint];
 
     for (int i=;i<=N;i++) k[i]=i;
     std::sort(k+, k+N+, cmp);
 
     q[U=]=p[k[]]; p[k[]]=;
     for (int i=;i<=N;i++)
     {
         if (p[k[i]]>q[U]) q[++U]=p[k[i]];
         p[k[i]]=U;
     }
 }
 void dfs(int u)
 {
     t[u]=insert(t[f[u]], , U, p[u]);
     if (d[u]>)
     {
         int lim=lg(d[u]);
         a[][u]=f[u];
         for (int i=;i<=lim;i++)
             a[i][u]=a[i-][a[i-][u]];
         for (int i=lim+;i<;i++)
             a[i][u]=;
     }
 
     for (edge * i=e[u];i;i=i->next) if (i->point!=f[u])
     {
         f[i->point]=u;
         d[i->point]=d[u]+;
         dfs(i->point);
     }
 }
 inline int lca(int u, int v)
 {
     if (d[u]<d[v]) swap(u, v);
     while (int dist=d[u]-d[v]) u=a[__builtin_ctz(dist)][u];
     if (u==v) return u;
     for (int i=;i>=;i--)
         if (a[i][u]!=a[i][v])
             u=a[i][u],
             v=a[i][v];
     return f[u];
 }
 inline int query(int a, int b, int k)
 {
     int c=lca(a, b), d=f[c];
     node * ta=t[a], * tb=t[b], * tc=t[c], * td=t[d];
     int l=, r=U, m;
 
     for ( ;l<r; )
     {
         m=(l+r)>>;
         if (ta->l->c+tb->l->c-tc->l->c-td->l->c>=k)
         {
             ta=ta->l; tb=tb->l; tc=tc->l; td=td->l;
             r=m;
         }
         else
         {
             k-=ta->l->c+tb->l->c-tc->l->c-td->l->c;
             ta=ta->r; tb=tb->r; tc=tc->r; td=td->r;
             l=m+;
         }
     }
 
     return q[l];
 }

又 R 又 T 一时爽