bzoj3223 文艺平衡树 Splay & Treap

平衡树做区间翻转

节点维护siz域用于查找当前第k个位置上的数，翻转打标记。
对于splay，翻转[L,R]只要把第L-1个位置转到根，第R+1个位置转到root->R的位置，对root->R->L打翻转标记。
对于合并式treap，翻转[L,R]只要分裂出L到R位置的树打标记即可。

Code:

Splay：

#include<bits/stdc++.h>using namespace std;const int maxn = 100005;const int INF  = 0x3f3f3f3f;struct node{    int key,siz;    bool fg;    node *ch[2],*fa;};node* root=NULL;int n,m;node *new_node(node *fa,int key){    node *t = new node;    t->ch[0]=t->ch[1] = NULL;    t->fa = fa;    t->key = key; t->siz = 1;    t->fg = 0;    return t;}#define siz(t) (t == NULL ? 0 : t->siz)void pushup(node *t){    t->siz = siz(t->ch[0])+siz(t->ch[1]) + 1;}void pushdown(node *t){    if(!t->fg)return;    t->fg=0;    swap(t->ch[0],t->ch[1]);    if(t->ch[0]) t->ch[0]->fg^=1;    if(t->ch[1]) t->ch[1]->fg^=1;}node *build(node* fa,int L,int R){    if(L>R)return NULL;    int mid=(L+R)>>1,key=mid-1;    node *t=new_node(fa,key);    t->ch[0]=build(t,L,mid-1);    t->ch[1]=build(t,mid+1,R);    pushup(t);    return t;}void order(node *t){    if(t == NULL)return;    pushdown(t);    order(t->ch[0]);    if(t->key >=1 && t->key <= n) printf("%d ",t->key);    order(t->ch[1]);}void rotate(node *x,bool d){    node *y=x->fa;    y->ch[!d]=x->ch[d];    if(x->ch[d]) x->ch[d]->fa=y;    x->fa = y->fa;    if(y->fa){        if(y == y->fa->ch[0])            y->fa->ch[0] = x;        else             y->fa->ch[1] = x;    }    x->ch[d] = y;y->fa=x;    pushup(y);pushup(x);}void splay(node *x,node *tar){    while( x->fa != tar){        node *y=x->fa;        if( x == y->ch[0]){            if(y->fa != tar && y == y->fa->ch[0])                rotate(y,1);            rotate(x,1);        }else{            if(y->fa != tar && y == y->fa->ch[1])                rotate(y,0);            rotate(x,0);        }    }    if( tar == NULL ) root=x;}node *find_kth(node *x,int kth){    pushdown(x);    int siz=siz(x->ch[0]);    if( siz+1 == kth ) return x;    if( kth <= siz )return find_kth(x->ch[0],kth);    return find_kth(x->ch[1],kth-siz-1);}void rev(int L,int R){    node *x=find_kth(root,L),*y=find_kth(root,R+2);    splay(x,NULL);    splay(y,root);    y->ch[0]->fg^=1;}int main(){    freopen("input.txt","r",stdin);    freopen("output1.txt","w",stdout);    scanf("%d%d",&n,&m);    root = build(NULL,1,n+2);    for(int L,R,i=1;i<=m;i++){        scanf("%d%d",&L,&R);        rev(L,R);    }    order(root);puts("");}

Treap:

#include<bits/stdc++.h>using namespace std;struct node{    int siz,key,pri;    bool fg;    node *L,*R;};node *root = NULL;int n,m;node* new_node(int key){    node *x = new node;    x->L = x->R = NULL;    x->key = key;    x->pri = rand();    x->siz = 1;    x->fg = 0;    return x;}#define siz(x) (x == NULL ? 0 : x->siz)void pushup(node *x){    x->siz=siz(x->L)+siz(x->R)+1;}void pushdown(node *x){    if(!x->fg)return;    x->fg=0;    swap(x->L,x->R);    if( x->L ) x->L->fg^=1;    if( x->R ) x->R->fg^=1;}node *merge(node *x,node *y){    if( x == NULL ) return y;    if( y == NULL ) return x;    pushdown(x);pushdown(y);    if( x->pri < y->pri ){        x->R = merge( x->R , y ); pushup(x); return x;    }else{        y->L = merge( x , y->L ); pushup(y); return y;    }}typedef pair<node*,node*>pii;pii split(node *x,int k){    if( x == NULL )return pii(NULL,NULL);    pushdown(x);    if( k <= siz(x->L) ){        pii tmp = split(x->L,k);        x->L=tmp.second;        pushup(x);        return pii(tmp.first,x);    } else {        pii tmp = split(x->R,k-siz(x->L)-1);        x->R=tmp.first;        pushup(x);        return pii(x,tmp.second);    }}node *build(int L,int R){    if(L>R)return NULL;    int mid=(L+R)>>1,key=mid-1;    node *x = new_node(key);    x->L = build(L,mid-1);    x->R = build(mid+1,R);    pushup(x);    return x;}void order(node *x){    if( x == NULL ) return;    pushdown(x);    order(x->L);    if(x->key >= 1 && x->key<=n)printf("%d ",x->key);    order(x->R);}void rev(int L,int R){    pii tmp1=split(root,R+1);    pii tmp2=split(tmp1.first,L);    tmp2.second->fg^=1;    root = NULL;    root = merge(tmp2.first,tmp2.second);    root = merge(root,tmp1.second);}int main(){    freopen("input.txt","r",stdin);    freopen("output2.txt","w",stdout);    srand(619);    scanf("%d%d",&n,&m);    root = build(1,n+2);    for(int L,R,i=1;i<=m;i++){        scanf("%d%d",&L,&R);        rev(L,R);    }    order(root);puts("");}