Bzoj 1861 [Zjoi2006]book Bookcase--splay

"Problem Analysis"

Template title.

Two virtual nodes, very convenient operation.

Code

#include <cstdio> #include <cstring> #include <cmath> #include <cstdlib> #include <map># Include <set> #include <queue> #include <string> #include <iostream> #include <algorithm> using namespace std; #define MAXN 500005#define inf 0x3f3f3f3f#define F (I,J,K) for (int i=j;i<=k;++i) #define D (i,j,k) fo R (int i=j;i>=k;--i) #define L ch[o][0] #define R ch[o][1] void Finout () {#ifndef Online_judge freopen ("In.txt", "R"    , stdin);//Freopen ("OUT.txt", "w", stdout);    #endif}int Getint () {int x=0,f=1; char Ch=getchar (); while (ch< ' 0 ' | |    Ch> ' 9 ') {if (ch== '-') f=-1; Ch=getchar ();}    while (ch>= ' 0 ' &&ch<= ' 9 ') {x=x*10+ch-' 0 '; Ch=getchar ();} return x*f;} int n,m;struct bit_tree{int a[maxn],b[maxn];void Add (int x,int y,int z) {for (int i=x;i<=n;i+=i& (-i)) b[i]+=z;for ( int i=y+1;i<=n;i+=i& (-i)) b[i]-=z;for (int i=x;i<=n;i+=i& (-i)) a[i]+= (n-x) *z;for (int i=y+1;i<=n;i+= i& (-i)) a[i]-= (n-y-1) *z;} INT getsum (int x) {int ret=0,tmp=0;for (int i=x;i;i-=i& (-i)) ret+=a[i];for (int i=x;i;i-=i& (-i)) Tmp+=b[i];return ret-(n-x-1) *tmp;} void Init () {memset (a,0,sizeof a); Memset (b,0,sizeof b);}} T;int Rt=0,a[maxn],s,t,id[maxn],cnt=0;char Opt[10];int num[maxn],ch[maxn][2],siz[maxn],fa[maxn],list[maxn];void Update (int o) {siz[o]=siz[l]+siz[r]+1;}    void rot (int x,int &k) {//cout<< "Rot" <<x<<endl;    int y=fa[x],z=fa[y],l,r; if (ch[y][0]==x) l=0;    else l=1;    r=l^1;    if (y==k) k=x;        else {if (ch[z][0]==y) ch[z][0]=x;    else ch[z][1]=x;    } fa[x]=z;    Fa[y]=x;    Fa[ch[x][r]]=y;    CH[Y][L]=CH[X][R];    Ch[x][r]=y; Update (y); Update (x);    }void splay (int x,int &k) {int y,z;        while (x!=k) {y=fa[x];z=fa[y];            if (y!=k) {if ((ch[z][0]==y) ^ (ch[y][0]==x)) rot (x,k);        else rot (y,k);    } rot (x,k); }}void ins (int & o,int X,int lst) {if (!o) {O=++cnt;fa[o]=lst;num[o]=x;siz[o]=1;list[o]=a[X-1];splay (O,RT); return;} if (X<num[o]) ins (ch[o][0],x,o); else ins (ch[o][1],x,o); update (o);} int find (int o,int x) {//cout<< "Qnum" <<num[o]<< "" "<<x<<endl; if (siz[l]+1==x) return o;if (siz[l]>=x) return find (l,x); else return find (r,x-siz[l]-1);} void print (int o) {if (!o) return;p rint (L);//cout<< "Now is" <<o<<endl;//cout<<L<< "" < <R<<endl;//cout<<num[o]<< "<<siz[o]<<endl;cout<<num[o]<<";p rint ( R);} void Mov (int o,int k) {splay (O,RT); int pre=find (rt,siz[l]), Nxt=find (rt,siz[l]+2); splay (PRE,RT); splay (Nxt,ch[rt][1]) ; ch[nxt][0]=0; Fa[o]=0;update (NXT); Update (pre); splay (NXT,RT);p re=find (rt,k-1); Nxt=find (rt,k); splay (PRE,RT); Splay (nxt,ch[rt][1]); ch[nxt][0]=o; Fa[o]=nxt;splay (O,RT);}    int main () {finout ();    scanf ("%d%d", &n,&m);    F (i,1,n) scanf ("%d", &a[i]), id[a[i]]=i+1;    F (i,0,n+1) ins (rt,i,0);//print (RT);//cout<<rt<<endl; F (i,1,m) {//PRint (RT);//cout<<endl;    scanf ("%s", opt);    scanf ("%d", &s);    if (opt[0]== ' Q ') {//cout<< "QUERY" <<endl;printf ("%d\n", A[find (rt,s+1)-1]);}    else if (opt[0]== ' A ') {//cout<< "ASK" <<endl;    Splay (ID[S],RT); printf ("%d\n", siz[ch[rt][0]]-1);} else if (opt[0]== ' T ') {//cout<< "TOP" <<endl; Mov (id[s],1+1);} else if (opt[0]== ' B ') {//cout<< "BOT" <<endl; Mov (id[s],n+1);} Else{t=getint (); splay (id[s],rt); int tmp=siz[ch[rt][0]]; Mov (id[s],tmp+t+1);}}}

　　

Bzoj 1861 [Zjoi2006]book Bookcase--splay