poj 3481 slpay 基础题

#include <iostream>#include <algorithm>#include <cstring>#include <cstdio>#define keyTree (ch[ ch[root][1] ][0])const int maxn = 1222222;const int inf = 0x3f3f3f3f;struct node { int id,priority;};struct SplayTree{int sz[maxn];int ch[maxn][2];int pre[maxn];int root , top1 , top2;int ss[maxn] , que[maxn];inline void Rotate(int x,int f) {int y = pre[x];ch[y][!f] = ch[x][f];pre[ ch[x][f] ] = y;pre[x] = pre[y];if(pre[x]) ch[ pre[y] ][ ch[pre[y]][1] == y ] = x;ch[x][f] = y;pre[y] = x;push_up(y);}inline void Splay(int x,int goal) {while(pre[x] != goal) {if(pre[pre[x]] == goal) {Rotate(x , ch[pre[x]][0] == x);} else {int y = pre[x] , z = pre[y];int f = (ch[z][0] == y);if(ch[y][f] == x) {Rotate(x , !f) , Rotate(x , f);} else {Rotate(y , f) , Rotate(x , f);}}}push_up(x);if(goal == 0) root = x;}inline void RotateTo(int k,int goal) {int x = root;while(sz[ ch[x][0] ] != k) {if(k < sz[ ch[x][0] ]) {x = ch[x][0];} else {k -= (sz[ ch[x][0] ] + 1);x = ch[x][1];}}Splay(x,goal);}inline void erase(int x) {int father = pre[x];int head = 0 , tail = 0;for (que[tail++] = x ; head < tail ; head ++) {ss[top2 ++] = que[head];if(ch[ que[head] ][0]) que[tail++] = ch[ que[head] ][0];if(ch[ que[head] ][1]) que[tail++] = ch[ que[head] ][1];}ch[ father ][ ch[father][1] == x ] = 0;push_up(father);}int NewNode(node c) {        int x;if (top2) x = ss[--top2];else x = ++top1;ch[x][0] = ch[x][1] = pre[x] = 0;sz[x] = 1;    client[x] = c;        return x;}inline void push_up(int x) {sz[x] = 1 + sz[ ch[x][0] ] + sz[ ch[x][1] ];}inline void init() {ch[0][0] = ch[0][1] = pre[0] = sz[0] = 0;root = top1 = 0;node c;c.priority = -inf;c.id= 0;int x = NewNode(c);root=1;c.priority = inf;x = NewNode(c);pre[x] = root;ch[root][1]=x;sz[root] = 2;        num = 0;push_up(ch[root][1]);push_up(root);}    int Insert(int rt,node c) {     if(c.priority<client[rt].priority) {        if(ch[rt][0]) {          return  Insert(ch[rt][0],c);        }  else {            int x = NewNode(c);            pre[x]=rt;   ch[rt][0]=x;            push_up(rt);            return x;        }     }     if(c.priority>client[rt].priority){        if(ch[rt][1]) return Insert( ch[rt][1] ,c);        else {            int x = NewNode(c);            pre[x] = rt;   ch[rt][1] = x;  push_up(rt);            return x;        }     }    }    int readIn(){     int op  ;     node c;   scanf("%d",&op);     if(op==0) return 0;     if(op==1)    {        scanf("%d%d",&c.id,&c.priority);        int xx=Insert(root,c);  Splay(xx,0);        num++;     }     if(op==2)  {        if(num>=1)  {        RotateTo(num-1,0);        RotateTo(num+1,root);        printf("%d\n",client[keyTree].id);        erase(keyTree);        num--;        } else puts("0"), root=1;     }     if(op==3)  {        if(num>=1)  {        RotateTo(0,0);  RotateTo(2,root);        printf("%d\n",client[keyTree].id);        erase(keyTree);        num--;        } else puts("0"),root=1;     }     return 1;    }    node client[maxn];    int num;}spt;int main() {    spt.init();while(spt.readIn());return 0;}