题面： 【模板】文艺平衡树（Splay）
题解：无
代码：
1 #include<cstdio> 2 #include<cstring> 3 #include<iostream> 4 #include<cstdlib> 5 using namespace std; 6 inline int rd(){ 7 int x=0,f=1;char c=getchar(); 8 while(c<'0'||c>'9'){if(c=='-')f=-1; c=getchar();} 9 while(c>='0'&&c<='9'){x=x*10+c-'0'; c=getchar();} 10 return f*x; 11 } 12 const int maxn=(1e5)+50; 13 int N,M,tot=0,val[maxn],siz[maxn],pr[maxn],rt=0,chd[maxn][3]; 14 int L,R,x,y,z; 15 bool fl[maxn]; 16 inline int New_node(int a){ 17 val[++tot]=a; 18 siz[tot]=1; 19 pr[tot]=rand(); 20 return tot; 21 } 22 inline void Pushup(int a){ 23 siz[a]=siz[chd[a][0]]+siz[chd[a][1]]+1; 24 return; 25 } 26 inline void Pushdown(int a){ 27 if(fl[a]){ 28 swap(chd[a][0],chd[a][1]); 29 if(chd[a][0])fl[chd[a][0]]^=1; 30 if(chd[a][1])fl[chd[a][1]]^=1; 31 fl[a]=0; 32 } 33 return; 34 } 35 inline int Merge(int a,int b){ 36 if(!a||!b)return (a+b); 37 if(pr[a]<pr[b]){ 38 Pushdown(a); 39 chd[a][1]=Merge(chd[a][1],b); 40 Pushup(a); 41 return a; 42 } 43 else{ 44 Pushdown(b); 45 chd[b][0]=Merge(a,chd[b][0]); 46 Pushup(b); 47 return b; 48 } 49 } 50 inline void Split(int now,int k,int &x,int &y){ 51 if(!now){x=y=0; return;} 52 Pushdown(now); 53 if(siz[chd[now][0]]+1<=k){ 54 x=now; 55 Split(chd[now][1],k-siz[chd[now][0]]-1,chd[now][1],y); 56 } 57 else { 58 y=now; 59 Split(chd[now][0],k,x,chd[now][0]); 60 } 61 Pushup(now); 62 return; 63 } 64 inline void Work(int now){ 65 if(!now)return; 66 Pushdown(now); 67 Work(chd[now][0]); 68 printf("%d ",val[now]); 69 Work(chd[now][1]); 70 return; 71 } 72 int main(){ 73 srand(20030304); 74 N=rd();M=rd(); 75 for(int i=1;i<=N;i++)rt=Merge(rt,New_node(i)); 76 while(M--){ 77 L=rd();R=rd(); 78 Split(rt,L-1,x,y); 79 Split(y,R-L+1,y,z); 80 fl[y]^=1; 81 rt=Merge(Merge(x,y),z); 82 } 83 Work(rt); 84 return 0; 85 }
By:AlenaNuna