BZOJ Tyvj 1729 文艺平衡树

 1 #include<iostream>
 2 #include<cstdio>
 3 using namespace std;
 4 int n,m,sz,rt;
 5 int fa[100005],c[100005][2],id[100005];
 6 int size[100005];
 7 bool rev[100005];
 8 
 9 void pushup(int  k){
10     int l=c[k][0],r=c[k][1];
11     size[k]=size[l]+size[r]+1;
12 }
13 void rotate(int x,int &k){
14     int y=fa[x],z=fa[y],l,r;
15     l=(c[y][1]==x); r=l^1;
16     if (k==y) k=x;
17     else c[z][c[z][1]==y]=x;
18     fa[c[x][r]]=y;fa[y]=x;fa[x]=z;
19     c[y][l]=c[x][r];c[x][r]=y; 
20     pushup(y);pushup(x);
21 }
22 
23 void splay(int x,int &k){
24     while (x!=k){
25         int y=fa[x],z=fa[y];
26         if (y!=k){
27         if ((c[y][0]==x)^(c[z][0]==y)) rotate(x,k);
28         else rotate(y,k);
29         }
30     rotate(x,k);
31     }
32 }
33 
34 void pushdown(int k){
35     int l=c[k][0],r=c[k][1];
36     if (rev[k]){
37         swap(c[k][0],c[k][1]);
38         rev[l]^=1; rev[r]^=1;
39         rev[k]=0;
40     }
41 }
42 
43 int find(int k,int rk){
44     pushdown(k);
45     int l=c[k][0],r=c[k][1];
46     if(size[l]+1==rk) return k;
47     if (size[l]>=rk) return find(l,rk);
48     return find(r,rk-size[l]-1);
49  }
50 
51 void rever(int l,int r){
52     int x=find(rt,l),y=find(rt,r+2);
53     splay(x,rt);splay(y,c[x][1]);
54     int z=c[y][0];
55     rev[z]^=1;
56 }
57 
58 void build(int l,int r,int f){
59     if(l>r) return;
60     int now=id[l],last=id[f];
61     if (l==r){
62         fa[now]=last;size[now]=1;
63         if (l<f)c[last][0]=now;
64         else c[last][1]=now;
65         return;
66     }
67     int mid=(l+r)>>1;now=id[mid];
68     build(l,mid-1,mid);build(mid+1,r,mid);
69     fa[mid]=last;pushup(mid);
70     c[last][mid>=f]=now;
71 }
72 
73 int main(){
74     scanf("%d%d",&n,&m);
75     for(int i=1;i<=n+2;i++)id[i]=++sz;
76     build(1,n+2,0); rt=(n+3)>>1;
77     for (int i=1;i<=m;i++){
78         int l,r;
79         scanf("%d%d",&l,&r);
80         rever(l,r);
81     }
82     for (int i=2;i<=n+1;i++) printf("%d ",find(rt,i)-1);
83 }