Robotic Sort HDU - 1890

​​http://acm.hdu.edu.cn/showproblem.php?pid=1890​​

伸展树模板

博客:​

​​http://dongxicheng.org/structure/splay-tree/​​

#include <cstdio>
#include <cstring>
#include <algorithm>
using namespace std;

struct node1
{
    int id;
    int val;
};

struct node2;
node2 *null;

struct node2
{
    node2 *fa,*ch[2];
    int sz,rev;
    void wipe()
    {
        fa=ch[0]=ch[1]=null;
        sz=1,rev=0;
    }
    void setc(node2* tmp,int d)
    {
        ch[d]=tmp;
        tmp->fa=this;
    }
    int getd()
    {
        return fa->ch[1]==this;
    }
    void reverse()
    {
        if(this==null) return;
        swap(ch[0],ch[1]);
        rev^=1;
    }
    void pushup()
    {
        if(this==null) return;
        sz=ch[0]->sz+ch[1]->sz+1;
    }
    void pushdown()
    {
        if(this==null) return;
        if(rev!=0)
        {
            ch[0]->reverse();
            ch[1]->reverse();
            rev=0;
        }
    }
};

node1 ary[100010];
node2* mp[100010];
node2 pool[100010];
node2 *root,*tail;
int n;

bool cmp(node1 n1,node1 n2)
{
    if(n1.val==n2.val) return n1.id<n2.id;
    else return n1.val<n2.val;
}

void build(node2 *&cur,int l,int r,node2 *fa)
{
    int m;
    if(l>r) return;
    m=(l+r)/2;
    cur=tail++;
    cur->wipe();
    cur->fa=fa;
    mp[m]=cur;
    build(cur->ch[0],l,m-1,cur);
    build(cur->ch[1],m+1,r,cur);
    cur->pushup();
}

void init()
{
    node2* tmp;
    int i;
    tail=pool;
    null=tail++;
    null->fa=null->ch[0]=null->ch[1]=null;
    null->sz=null->rev=0;
    tmp=tail++;
    tmp->wipe();
    root=tmp;
    tmp=tail++;
    tmp->wipe();
    root->setc(tmp,1);
    build(root->ch[1]->ch[0],1,n,root->ch[1]);
    root->ch[1]->pushup();
    root->pushup();
}

void rotate(node2 *cur)
{
    node2 *f,*ff;
    int c,cc;
    f=cur->fa,ff=cur->fa->fa;
    f->pushdown();
    cur->pushdown();
    c=cur->getd(),cc=f->getd();
    f->setc(cur->ch[!c],c);
    cur->setc(f,!c);
    if(ff->ch[cc]==f) ff->setc(cur,cc);
    else cur->fa=ff;
    f->pushup();
}

void splay(node2 *&root,node2 *cur,node2 *tar)
{
    while(cur->fa!=tar)
    {
        if(cur->fa->fa==tar) rotate(cur);
        else
        {
            cur->fa->fa->pushdown();
            cur->fa->pushdown();
            cur->pushdown();
            if(cur->getd()==cur->fa->getd()) rotate(cur->fa);
            else rotate(cur);
            rotate(cur);
        }
    }
    cur->pushup();
    if(tar==null) root=cur;
}

node2 *getkth(node2 *r,int k)
{
    node2 *cur;
    cur=r;
    cur->pushdown();
    while(cur->ch[0]->sz+1!=k)
    {
        if(cur->ch[0]->sz+1>k)
        {
            cur=cur->ch[0];
        }
        else
        {
            k-=(cur->ch[0]->sz+1);
            cur=cur->ch[1];
        }
        cur->pushdown();
    }
    return cur;
}

int main()
{
    int i,sz;
    while(scanf("%d",&n)!=EOF)
    {
        if(n==0) break;
        for(i=1;i<=n;i++)
        {
            ary[i].id=i;
            scanf("%d",&ary[i].val);
        }
        init();
        sort(ary+1,ary+n+1,cmp);
        for(i=1;i<=n;i++)
        {
            splay(root,mp[ary[i].id],null);
            sz=root->ch[0]->sz;
            printf("%d",sz);
            if(i<n) printf(" ");
            else printf("\n");
            splay(root,getkth(root,i),null);
            splay(root,getkth(root,sz+2),root);
            root->ch[1]->ch[0]->reverse();
        }
    }
    return 0;
}