SplayTree实现_简化版
（1）
template<class DataType>
class SplayTree{
#define MAXN 1000010
private:
int ch[MAXN][2],pre[MAXN],pool[MAXN];
DataType key[MAXN];
int top,root,tot;
int malloc(DataType dt){
int x;
if(top!=0) x = pool[--top];
else x = ++tot;
key[x] = dt;
return x;
}
void free(int x){
ch[x][0] = ch[x][1] = pre[x] = 0;
pool[top++] = x;
}
void rotate(int x,int f){//f == 0 为zag f == 1 为zig
int y = pre[x]; int z = pre[y];
ch[y][!f] = ch[x][f];
if(ch[y][!f]) pre[ch[y][!f]] = y;
ch[x][f] = y;
pre[y] = x;
if(z) ch[z][0]==y?ch[z][0] = x:ch[z][1] = x;
pre[x] = z;
}
void splay(int x,int &rt){
int y,z;
while(pre[x]){
y = pre[x]; z = pre[y];
if(!z){
rotate(x,ch[y][0]==x);
}else{
int f = ch[z][0]==y;
if(ch[y][!f]==x){
rotate(y,f); rotate(x,f);
}else{
rotate(x,!f); rotate(x,f);
}
}
}
rt = x;
}
int find_help(DataType k,int rt){
if(!rt) return 0;
if(k==key[rt])return rt;
return k<key[rt]?find_help(k,ch[rt][0]):find_help(k,ch[rt][1]);
}
int findmax_help(int rt){
int x = rt;
while(x&&ch[x][1]) x = ch[x][1];
return x;
}
int findmin_help(int rt){
int x = rt;
while(x&&ch[x][0]) x = ch[x][0];
return x;
}
int join(int rt1,int rt2){
if(!rt1) return rt2;
if(!rt2) return rt1;
int x = findmax_help(rt1);
splay(x,rt1);
ch[rt1][1] = rt2;
pre[rt2] = rt1;
return rt1;
}
int split(DataType k,int &rt,int &rt1,int &rt2){
int x = find_help(k,rt);
if(!x) return 0;
splay(x,rt);
rt1 = ch[rt][0]?ch[rt][0]:0;
pre[rt1] = 0;
rt2 = ch[rt][1]?ch[rt][1]:0;
pre[rt2] = 0;
return rt;
}
int insert_help(DataType k,int &rt,int father){
if(!rt){
rt = malloc(k);
pre[rt] = father;
return rt;
}
return insert_help(k,ch[rt][!(k<key[rt])],rt);
}
public:
void insert(DataType k){
int x = insert_help(k,root,0);
splay(x,root);
}
void remove(DataType k){
int rt1,rt2;
int x = split(k,root,rt1,rt2);
if(!x) return;
free(x);
root = join(rt1,rt2);
}
int findmax(DataType &k){
int x = findmax_help(root);
if(x) splay(x,root);
k = key[x];
return x;
}
int findmin(DataType &k){
int x = findmin_help(root);
if(x) splay(x,root);
k = key[x];
return x;
}
};
（2）
template<class DataType>
class SplayTree{
#define MAXN 1000010
private:
int ch[MAXN][2],pre[MAXN],pool[MAXN];
DataType key[MAXN];
int top,root,tot;
int malloc(DataType dt){
int x;
if(top!=0) x = pool[--top];
else x = ++tot;
key[x] = dt;
return x;
}
void free(int x){
ch[x][0] = ch[x][1] = pre[x] = 0;
pool[top++] = x;
}
void rotate(int x,int f){//f == 0 为zag f == 1 为zig
int y = pre[x]; int z = pre[y];
ch[y][!f] = ch[x][f];
if(ch[y][!f]) pre[ch[y][!f]] = y;
ch[x][f] = y;
pre[y] = x;
if(z) ch[z][0]==y?ch[z][0] = x:ch[z][1] = x;
pre[x] = z;
}
void splay(int x,int &rt){
int y,z;
while(pre[x]){
y = pre[x]; z = pre[y];
if(!z){
rotate(x,ch[y][0]==x);
}else{
int f = ch[z][0]==y;
if(ch[y][!f]==x){
rotate(y,f); rotate(x,f);
}else{
rotate(x,!f); rotate(x,f);
}
}
}
rt = x;
}
int find_help(DataType k,int rt){
if(!rt) return 0;
if(k==key[rt])return rt;
return k<key[rt]?find_help(k,ch[rt][0]):find_help(k,ch[rt][1]);
}
int findmax_help(int rt){
int x = rt;
while(x&&ch[x][1]) x = ch[x][1];
return x;
}
int findmin_help(int rt){
int x = rt;
while(x&&ch[x][0]) x = ch[x][0];
return x;
}
int insert_help(DataType k,int &rt,int father){
if(!rt){
rt = malloc(k);
pre[rt] = father;
return rt;
}
return insert_help(k,ch[rt][!(k<key[rt])],rt);
}
void remove_help(DataType k,int &rt,int father){
if(!rt) return;
if(k==key[rt]){
if(ch[rt][0]==0||ch[rt][1]==0){
int x = rt;
rt = ch[rt][0]+ch[rt][1];
if(rt){ pre[rt] = father; splay(rt,root); }
free(x);
return;
}
int x = findmin_help(ch[rt][1]);
key[rt] = key[x];
remove_help(key[rt],ch[rt][1],rt);
splay(rt,root);
}
remove_help(k,ch[rt][!(k<key[rt])],rt);
}
public:
void insert(DataType k){
int x = insert_help(k,root,0);
splay(x,root);
}
void remove(DataType k){
remove_help(k,root,0);
}
int findmax(DataType &k){
int x = findmax_help(root);
if(x) splay(x,root);
k = key[x];
return x;
}
int findmin(DataType &k){
int x = findmin_help(root);
if(x) splay(x,root);
k = key[x];
return x;
}
};