1 #include<cstdio>
2 #include<cstring>
3 #include<iostream>
4 #include<algorithm>
5 #include<vector>
6 using namespace std;
7 struct NODE{
8 NODE *ls,*rs;
9 int r,s,v;
10 int rev;
11 #define size(x) ((x)?(x)->s:0)
12 NODE(int v=0):v(v){
13 r=rand();
14 ls=rs=NULL;
15 s=1;
16 rev=0;
17 }
18 void reverse(){
19 if(!this) return;
20 swap(ls,rs);
21 rev^=1;
22 }
23 void pushdown(){
24 if(!this) return;
25 if(rev){
26 ls->reverse();
27 rs->reverse();
28 rev^=1;
29 }
30 }
31 void mt(){
32 s=1+size(ls)+size(rs);
33 }
34 };
35
36 typedef NODE *pnode;
37 typedef pair<NODE*,NODE*>droot;
38 NODE *merge(NODE *a,NODE *b){//treap为了满足中序序列，左右子树不能交换
39 if(!a) return b;
40 if(!b) return a;
41 if(a->r < b->r){//小根堆
42 a->pushdown();
43 a->rs=merge(a->rs,b);
44 a->mt();
45 return a;
46 }
47 else {
48 b->pushdown();
49 b->ls=merge(a,b->ls);
50 b->mt();
51 return b;
52 }
53 }
54 droot split(NODE *x,int k){
55 if(!x) return droot(NULL,NULL);
56 x->pushdown();
57 droot r;
58 if(size(x->ls) >= k){
59 r=split(x->ls,k);
60 x->ls=r.second;
61 x->mt();
62 r.second=x;
63 }
64 else {
65 r=split(x->rs,k-size(x->ls)-1);
66 x->rs=r.first;
67 x->mt();
68 r.first=x;
69 }
70 return r;
71 }
72 //名次树用的普通写法
73 int kth(NODE *x,int k){//
74 if(!x || k<=0 || k>size(x)) return 0;
75 int s=size(x->rs);
76 if(k == s+1) return x->v;
77 else if(k <= s) return kth(x->ls,k);
78 else return kth(x->rs,k-size(x->ls)-1);
79 }
80 int rank(NODE *x,int v){
81 if(!x) return 0;
82 if(v < x->v) return rank(x->ls,v);
83 else return rank(x->rs,v)+size(x->ls)+1;
84 }
85 NODE *insert(NODE *root,int v){
86 int k=rank(root,v);
87 droot x=split(root,k);
88 NODE *o=new NODE(v);
89 return merge(merge(x.first,o),x.second);
90 }
91 NODE *build(int *a,int n){
92 pnode *stk=new pnode[n];
93 NODE *last;
94 int tp=0;
95 for(int i=1;i<=n;i++){
96 NODE *p=new NODE(i);
97 last=NULL;
98 while(tp && stk[tp-1]->r > p->r){
99 stk[tp-1]->mt();
100 last=stk[tp-1];
101 stk[--tp]=NULL;
102 }
103 if(tp) stk[tp-1]->rs=p;
104 p->ls=last;
105 stk[tp++]=p;
106 }
107 while(tp) stk[--tp]->mt();
108 NODE *r=stk[0];
109 delete []stk;
110 return r;
111 }
112
113 void dfs(NODE *u){
114 if(!u) return;
115 u->pushdown();
116 dfs(u->ls);
117 printf("%d ",u->v);
118 dfs(u->rs);
119 }
120
121 int n,m;
122 int d[100010];
123 int main(){
124 freopen("sph.in", "r", stdin);
125 freopen("sph.out", "w", stdout);
126 scanf("%d %d",&n,&m);
127 NODE *t=build(d,n);
128 while(m--){
129 int l,r;
130 scanf("%d %d",&l,&r);
131 droot p1=split(t,l-1);
132 droot p2=split(p1.second,r-l+1);
133 p2.first->reverse();
134 t=merge(p1.first,merge(p2.first,p2.second));
135 }
136 dfs(t);
137 return(0);
138 }
