题面

题解

\(FHQ\ Treap\)比起\(Splay\)还是稍微好写一点……就是老是忘了要下穿标记……

//minamoto#include
    
     #define R register#define inline __inline__ __attribute__((always_inline))#define fp(i,a,b) for(R int i=(a),I=(b)+1;i
     
      I;--i)#define go(u) for(int i=head[u],v=e[i].v;i;i=e[i].nx,v=e[i].v)template
      
       inline bool cmax(T&a,const T&b){return a
       
        
         inline bool cmin(T&a,const T&b){return a>b?a=b,1:0;}using namespace std;char buf[1<<21],*p1=buf,*p2=buf;inline char getc(){return p1==p2&&(p2=(p1=buf)+fread(buf,1,1<<21,stdin),p1==p2)?EOF:*p1++;}int read(){    R int res,f=1;R char ch;    while((ch=getc())>'9'||ch<'0')(ch=='-')&&(f=-1);    for(res=ch-'0';(ch=getc())>='0'&&ch<='9';res=res*10+ch-'0');    return res*f;}char sr[1<<21],z[20];int K=-1,Z=0;inline void Ot(){fwrite(sr,1,K+1,stdout),K=-1;}void print(R int x){    if(K>1<<20)Ot();if(x<0)sr[++K]='-',x=-x;    while(z[++Z]=x%10+48,x/=10);    while(sr[++K]=z[Z],--Z);sr[++K]=' ';}unsigned int aaa=19260817;inline unsigned int rd(){aaa^=aaa>>15,aaa+=aaa<<12,aaa^=aaa>>3;return aaa;}struct node;typedef node* ptr;const int N=1e5+5;inline void swap(R ptr &s,R ptr &t){R ptr p=s;s=t,t=p;}struct node{    ptr lc,rc;int t,sz,v;unsigned int pr;    inline node();    inline ptr init(R int val){return pr=rd(),v=val,sz=1,t=0,this;}    inline ptr ppd(){return swap(lc,rc),t^=1,this;}    inline ptr pd(){if(t)lc->ppd(),rc->ppd(),t=0;return this;}    inline ptr upd(){return sz=lc->sz+rc->sz+1,this;}}e[N],*rt=e,*pp=e;inline node::node(){lc=rc=e;}inline ptr newnode(R int v){return (++pp)->init(v);}void split(ptr p,int k,ptr &s,ptr &t){    if(p==e)return s=t=e,void();    if(p->pd()->lc->sz
         
          rc,k-p->lc->sz-1,p->rc,t); else t=p,split(p->lc,k,s,p->lc); p->upd();}ptr merge(ptr s,ptr t){ if(s==e)return t;if(t==e)return s; if(s->pd()->pr
          
           pd()->pr)return s->rc=merge(s->rc,t),s->upd(); return t->lc=merge(s,t->lc),t->upd();}void rev(int l,int r){ ptr s,t,p,q; split(rt,r,s,t),split(s,l-1,p,q); rt=merge(merge(p,q->ppd()),t);}void dfs(ptr p){ if(p->pd()->lc!=e)dfs(p->lc); print(p->v); if(p->rc!=e)dfs(p->rc);}int main(){// freopen("testdata.in","r",stdin); int n=read(),m=read(),l,r; fp(i,1,n)rt=merge(rt,newnode(i)); while(m--)l=read(),r=read(),rev(l,r); return dfs(rt),Ot(),0;}