题目

  1 #include<iostream>
  2 #include<cstring>
  3 #include<cstdlib>
  4 #include<cstdio>
  5 using namespace std;
  6 inline int read(){
  7     int sum(0);
  8     char ch(getchar());
  9     while(ch<‘0‘||ch>‘9‘)
 10         ch=getchar();
 11     while(ch>=‘0‘&&ch<=‘9‘){
 12         sum=sum*10+ch-‘0‘;
 13         ch=getchar();
 14     }
 15     return sum;
 16 }
 17 int n,m,top;
 18 struct node{
 19     int v,key,size,mark;
 20     node *ch[2];
 21     node(int x=0):size(1),key(rand()),mark(0),v(x){
 22         ch[0]=ch[1]=NULL;
 23     }
 24     inline void revs();
 25     inline void pushup();
 26     inline void pushdown(){
 27         if(mark){
 28             if(ch[0])
 29                 ch[0]->revs();
 30             if(ch[1])
 31                 ch[1]->revs();
 32             mark=0;
 33         }
 34     }
 35 }*root,*st[100005];
 36 typedef pair<node*,node*>p;
 37 inline void swp(node *x,node *y){
 38     node *tmp(x);
 39     x=y;
 40     y=tmp;
 41 }
 42 inline int get_size(node *x){
 43     if(x==NULL)
 44         return 0;
 45     return x->size;
 46 }
 47 inline void node::revs(){
 48     mark^=1;
 49     swap(ch[0],ch[1]);
 50 }
 51 inline void node::pushup(){
 52     size=1;
 53     size+=get_size(ch[0])+get_size(ch[1]);
 54 }
 55 inline node* build(){
 56     node *x,*las;
 57     for(int i=1;i<=n;i++){
 58         x=new node(i);
 59         las=NULL;
 60         while(top&&st[top]->key>x->key){
 61             st[top]->pushup();
 62             las=st[top];
 63             st[top--]=NULL;
 64         }
 65         if(top)
 66             st[top]->ch[1]=x;
 67         x->ch[0]=las;
 68         st[++top]=x;
 69     }
 70     while(top)
 71         st[top--]->pushup();
 72     return st[1];
 73 }
 74 inline node* merge(node *x,node *y){
 75     if(x==NULL)
 76         return y;
 77     if(y==NULL)
 78         return x;
 79     if(x->key<y->key){
 80         x->pushdown();
 81         x->ch[1]=merge(x->ch[1],y);
 82         x->pushup();
 83         return x;
 84     }
 85     else{
 86         y->pushdown();
 87         y->ch[0]=merge(x,y->ch[0]);
 88         y->pushup();
 89         return y;
 90     }
 91 }
 92 inline p split(node *x,int k){
 93     if(!x)
 94         return p(NULL,NULL);
 95     p y;
 96     x->pushdown();
 97     if(get_size(x->ch[0])>=k){
 98         y=split(x->ch[0],k);
 99         x->ch[0]=y.second;
100         x->pushup();
101         y.second=x;
102     }
103     else{
104         y=split(x->ch[1],k-get_size(x->ch[0])-1);
105         x->ch[1]=y.first;
106         x->pushup();
107         y.first=x;
108     }
109     return y;
110 }
111 inline int rk(node *rt,int x){
112     if(!rt)
113         return 0;
114     return x<rt->v?rk(rt->ch[0],x):rk(rt->ch[1],x)+get_size(rt->ch[0])+1;
115 }
116 inline int kth(int k){
117     p x(split(root,k-1)),y(split(x.second,1));
118     node *tmp(y.first);
119     root=merge(merge(x.first,tmp),y.second);
120     return tmp->v;
121 }
122 inline void insert(int x){
123     int k(rk(root,x));
124     p tp(split(root,k));
125     node *tmp(new node(x));
126     root=merge(merge(tp.first,tmp),tp.second);
127 }
128 inline void print(node *x){
129     if(!x)
130         return;
131     x->pushdown();
132     print(x->ch[0]);
133     printf("%d ",x->v);
134     print(x->ch[1]);
135 }
136 inline int gg(){
137     srand(time(NULL));
138     n=read(),m=read();
139     root=build();
140     for(int i=1;i<=m;i++){
141         int x(read()),y(read());
142         if(x==y)
143             continue;
144         p tmp1(split(root,x-1)),tmp2(split(tmp1.second,y-x+1));
145         tmp2.first->revs();
146         root=merge(tmp1.first,merge(tmp2.first,tmp2.second));
147     }
148     print(root);
149 }
150 int k(gg());
151 int main(){;}