Splay解决区间问题[区间切割，区间翻转]

区间翻转：由于以root为根的树的中序遍历表示该区间，那么翻转只要递归的交换左右子树即可，加入lazy思想，降低时间复杂度。

Tips：做区间翻转的时候rev[rt]的含义是——以rt为根的子树所表示的区间是否将要被翻转，目前并没有执行翻转操作，如果改成先翻转，再标记，就会出现大问题。

Code：没用的push_down写多了。

/*http://acm.hdu.edu.cn/showproblem.php?pid=3487*/
/*splay区间切割+翻转*/
#include<iostream>
#include<cstdio>
#include<cstring>
using namespace std;
const int MAXN = 333333;
#define m_set(ptr,v,type,size) memset(ptr,v,sizeof(type)*size)
#define loop(begin,end) for(int i=begin;i<end;i++)
class SplayTree{
    #define l(x) (ch[x][0])
    #define r(x) (ch[x][1])
    #define mid(x,y) ((x+y)>>1)
public:
    int ch[MAXN][2],pre[MAXN];
    int sz[MAXN],val[MAXN],rev[MAXN],a[MAXN];
    int root,tot;
    void init(){
        m_set(ch,0,int,MAXN*2);
        m_set(pre,0,int,MAXN);
        m_set(sz,0,int,MAXN);
        m_set(val,0,int,MAXN);
        m_set(rev,0,int,MAXN);
        root = tot = 0;
    }
    void read(int n){
        a[1] = a[n+2] = 0;
        loop(2,n+2){ a[i] = i-1; }
    }
    void push_up(int rt){
        sz[rt] = sz[l(rt)]+sz[r(rt)]+1;
    }
    void swap(int &x,int &y){
        int tmp = x;
        x = y;
        y = tmp;
    }
    void push_down(int rt){
        if(rt&&rev[rt]){
            swap(l(rt),r(rt));
            if(l(rt)) rev[l(rt)] ^= 1;
            if(r(rt)) rev[r(rt)] ^= 1;
            rev[rt] = 0;
        }
    }
    void rotate(int x,int f){
        int y = pre[x];
        push_down(x);
        push_down(y);
        ch[y][!f] = ch[x][f];
        if(ch[y][!f]) pre[ch[y][!f]] = y;
        push_up(y);
        if(pre[y]) ch[pre[y]][r(pre[y])==y] = x;
        pre[x] = pre[y];
        ch[x][f] = y;
        pre[y] = x;
    }
    void splay(int x,int goal){
        push_down(x);
        while(pre[x]!=goal){
            int y = pre[x], z = pre[pre[x]];
            if(z==goal){
                rotate(x,l(y)==x);
            }else{
                int f = l(z)==y;
                if(ch[y][!f]==x){
                    rotate(y,f); rotate(x,f);
                }else{
                    rotate(x,!f); rotate(x,f);
                }
            }
        }
        push_up(x);
        if(goal==0) root = x;
    }
    void rotateTo(int k,int goal){
        int x = root;
        while(1){
            push_down(x);
            int tmp = sz[l(x)]+1;
            if(k==tmp) break;
            else if(k<tmp) x = l(x);
            else{
                k -= tmp;
                x = r(x);
            }
        }
        splay(x,goal);
    }
    void buildTree(int l,int r,int &rt,int f){
        if(l>r)return;
        int m = mid(l,r);
        rt = ++tot;
        val[rt] = a[m];
        pre[rt] = f;
        buildTree(l,m-1,l(rt),rt);
        buildTree(m+1,r,r(rt),rt);
        push_up(rt);
    }
    void rangeCut(int l,int r,int goal){
        rotateTo(l-1,0);
        rotateTo(r+1,root);
        push_down(r(root));
        int x = l(r(root));
        l(r(root)) = 0;
        pre[x] = 0;
        push_up(r(root));
        push_up(root);
        rotateTo(goal,0);
        rotateTo(goal+1,root);
        push_down(r(root));
        l(r(root)) = x;
        pre[x] = r(root);
        push_up(r(root));
        push_up(root);
    }
    void rangeFlip(int l,int r){
        rotateTo(l-1,0);
        rotateTo(r+1,root);
        push_down(r(root));
        int x = l(r(root));
        rev[x] ^= 1;
    }
    void dfs(int rt,int &size){
        if(!rt) return;
        push_down(rt);
        dfs(l(rt),size);
        a[size++] = val[rt];
        dfs(r(rt),size);
    }
    /////////////////debug///////////////////////

}spt;
int main(){
    int n,m;
    while(scanf("%d%d",&n,&m),!(n<0&&m<0)){
        spt.init();
        spt.read(n);
        spt.buildTree(1,n+2,spt.root,0);
        char op[5]; int a,b,c;
        while(m--){
            scanf("%s%d%d",op,&a,&b);
            if(op[0]=='C'){
                scanf("%d",&c);
                spt.rangeCut(a+1,b+1,c+1);
            }else{
                spt.rangeFlip(a+1,b+1);
            }
        }
        n = 0;
        spt.dfs(spt.root,n);
        loop(1,n-1){
            if(i!=1)printf(" ");
            printf("%d",spt.a[i]);
        }
        printf("\n");
    }
    return 0;
}