3223: Tyvj 1729 文艺平衡树

#include<cstdio>
#include<algorithm>
using namespace std;
const int N=1e5+10; 
inline const int read(){
    register int x=0,f=1;
    register char ch=getchar();
    while(ch>‘9‘||ch<‘0‘){if(ch==‘-‘)f=-1;ch=getchar();}
    while(ch>=‘0‘&&ch<=‘9‘){x=x*10+ch-‘0‘;ch=getchar();}
    return x*f;
}
int n,m,sz,rt;
int fa[N],c[N][2],id[N];
int size[N];
bool rev[N];
void pushup(int k){
    int l=c[k][0],r=c[k][1];
    size[k]=size[l]+size[r]+1;
}
void pushdown(int k){
    int l=c[k][0],r=c[k][1];
    if(rev[k]){
        swap(c[k][0],c[k][1]);
        rev[l]^=1;rev[r]^=1;
        rev[k]=0;
    }
}
void rotate(int x,int &k){
    int y=fa[x],z=fa[y],l,r;
    if(c[y][0]==x)l=0;else l=1;r=l^1;
    if(y==k)k=x;
    else {if(c[z][0]==y)c[z][0]=x;else c[z][1]=x;}
    fa[x]=z;fa[y]=x;fa[c[x][r]]=y;
    c[y][l]=c[x][r];c[x][r]=y;
    pushup(y);pushup(x);
}
void splay(int x,int &k){
    while(x!=k){
        int y=fa[x],z=fa[y];
        if(y!=k){
            if(c[y][0]==x^c[z][0]==y)rotate(x,k);
            else rotate(y,k);
        }
        rotate(x,k);
    }
}
int find(int k,int rank){
    pushdown(k);
    int l=c[k][0],r=c[k][1];
    if(size[l]+1==rank)return k;
    else if(size[l]>=rank)return find(l,rank);
    else return find(r,rank-size[l]-1);
}
void rever(int l,int r){
    int x=find(rt,l),y=find(rt,r+2);
    splay(x,rt);splay(y,c[x][1]);
    int z=c[y][0];
    rev[z]^=1;
}
void build(int l,int r,int f){
    if(l>r) return;
    int now=id[l],last=id[f];
    if(l==r){
        fa[now]=last;size[now]=1;
        if(l<f)c[last][0]=now;
        else c[last][1]=now;
        return;
    }
    int mid=(l+r)>>1;now=id[mid];
    build(l,mid-1,mid);build(mid+1,r,mid);
    fa[now]=last;pushup(mid);
    if(mid<f)c[last][0]=now;
    else c[last][1]=now;
}
int main(){
    n=read();m=read();
    for(int i=1;i<=n+2;i++) id[i]=++sz;
    build(1,n+2,0);rt=(n+3)>>1;
    for(int i=1;i<=m;i++){
        int l=read(),r=read();
        rever(l,r);
    }
    for(int i=2;i<=n+1;i++) printf("%d ",find(rt,i)-1);
    return 0;
}