【模板】无旋Treap（FHQ）

如题，这是一个模板。。。

 #include <algorithm>
 #include <iostream>
 #include <cstring>
 #include <cstdio>
 #include <cctype>

 inline void read(int & x)
 {
     x = ;
     int k = ;
     char c = getchar();
     while (!isdigit(c))
         if (c == '-') c = getchar(), k = -;
         else c = getchar();
     while (isdigit(c))
         x = (x << ) + (x << ) + (c ^ ),
         c = getchar();
     x *= k;
 }

 const int MAXN = ;
 int seed = ;
 int m, x, tot, opt, rt = ;
 int siz[MAXN], val[MAXN], rnd[MAXN], son[MAXN][];

 inline int Rand()
 {
     return seed = (int)seed * 482711LL % ;
 }

 inline void Pushup(int u)
 {
     siz[u] = siz[son[u][]] + siz[son[u][]] + ;
 }

 inline int New(int x)
 {
     siz[++tot] = ;
     val[tot] = x;
     rnd[tot] = Rand();
     son[tot][] = son[tot][] = ;
     return tot;
 }

 inline void Split(int u, int x, int &a, int &b)
 {
     if (!u) { a = b = ; return; }
     if (val[u] <= x) a = u, Split(son[u][], x, son[a][], b);
     else b = u, Split(son[u][], x, a, son[b][]);
     Pushup(u);
 }

 inline void Split_siz(int u, int k, int &a, int &b)
 {
     if (!u) { a = b = ; return; }
     if (k <= siz[son[u][]]) b = u, Split_siz(son[u][], k, a, son[b][]);
     else a = u, Split_siz(son[u][], k - siz[son[u][]] - , son[a][], b);
     Pushup(u);
 }

 inline void Merge(int & u, int a, int b)
 {
     if (!a || !b) { u = a | b; return; }
     if (rnd[a] < rnd[b]) u = a, Merge(son[u][], son[a][], b);
     else u = b, Merge(son[u][], a, son[b][]);
     Pushup(u);
 }

 inline int Findkth(int u, int k)
 {
     while (siz[son[u][]] +  != k)
         if (siz[son[u][]] >= k) u = son[u][];
         else k -= siz[son[u][]] + , u = son[u][];
     return u;
 }

 inline void Insert(int x)
 {
     int a = , b = , c = ;
     c = New(x);
     Split(rt, x, a, b);
     Merge(a, a, c);
     Merge(rt, a, b);
 }

 inline void Delete(int x)
 {
     int a = , b = , c = ;
     Split(rt, x, a, b);
     Split(a, x - , a, c);
     Merge(c, son[c][], son[c][]);
     Merge(a, a, c);
     Merge(rt, a, b);
 }

 inline void Getrank(int x)
 {
     int a = , b = ;
     Split(rt, x - , a, b);
     printf("%d\n", siz[a] + );
     Merge(rt, a, b);
 }

 inline void Getkth(int k)
 {
     int a = , b = , c = ;
 //·½·¨1£ºÓú¯ÊýÄõÚk´ó
     printf("%d\n", val[Findkth(rt, k)]);
     return;

 //·½·¨2£º°´siz·ÖÁÑÄóöc
     Split_siz(rt, k, a, b);
     Split_siz(a, k - , a, c);
     printf("%d\n", val[c]);
     Merge(a, a, c);
     Merge(rt, a, b);
 }

 inline void Pre(int x)
 {
     int a = , b = ;
     Split(rt, x - , a, b);
     printf("%d\n", val[Findkth(a, siz[a])]);
     Merge(rt, a, b);
 }

 inline void Suf(int x)
 {
     int a = , b = ;
     Split(rt, x, a, b);
     printf("%d\n", val[Findkth(b, )]);
     Merge(rt, a, b);
 }

 signed main()
 {
     read(m);
     for (int i = ; i <= m; ++i)
     {
         read(opt), read(x);
         if (opt == ) Insert(x);
         if (opt == ) Delete(x);
         if (opt == ) Getrank(x);
         if (opt == ) Getkth(x);
         if (opt == ) Pre(x);
         if (opt == ) Suf(x);
     }
     return ;
 }