bzoj2258 pku2758 Checking the Text 文本校对（Hash+二分+splay）

#include <cstdio>
#include <cstring>
#include <algorithm>
#include <queue>
using namespace std;
#define ull unsigned long long
#define N 55010
#define k1 11113
inline int read(){
int x=0,f=1;char ch=getchar();
while(ch<'0'||ch>'9'){if(ch=='-')f=-1;ch=getchar();}
while(ch>='0'&&ch<='9') x=x*10+ch-'0',ch=getchar();
return x*f;
}
int n,m,fa
,sz
,c
[2],rt=0,v
;
ull hs
,bin
;char s
;
inline void update(int p){
int l=c[p][0],r=c[p][1];
sz[p]=sz[l]+sz[r]+1;
hs[p]=hs[l]*bin[sz[r]+1]+v[p]*bin[sz[r]]+hs[r];
}
inline void build(int &p,int l,int r){
int mid=l+r>>1;p=mid;v[p]=s[p-1];
if(l<mid) build(c[p][0],l,mid-1),fa[c[p][0]]=p;
if(r>mid) build(c[p][1],mid+1,r),fa[c[p][1]]=p;update(p);
}
inline int find(int p,int k){
if(sz[c[p][0]]+1==k) return p;
if(k<=sz[c[p][0]]) return find(c[p][0],k);
return find(c[p][1],k-sz[c[p][0]]-1);
}
inline void rotate(int x,int &k){
int y=fa[x],z=fa[y],l=x==c[y][1],r=l^1;
if(y==k) k=x;
else c[z][y==c[z][1]]=x;
fa[c[x][r]]=y;fa[y]=x;fa[x]=z;
c[y][l]=c[x][r];c[x][r]=y;update(y);update(x);
}
inline void splay(int x,int &k){
while(x!=k){
int y=fa[x],z=fa[y];
if(y!=k){
if(x==c[y][1]^y==c[z][1]) rotate(x,k);
else rotate(y,k);
}rotate(x,k);
}
}
inline int split(int xx,int yy){
int x=find(rt,xx),y=find(rt,yy);
splay(x,rt);splay(y,c[x][1]);return c[y][0];
}
inline ull cal(int l,int r){
int x=split(l-1,r+1);return hs[x];
}
inline int lcp(int x,int y){
int l=0,r=min(n-x+1,n-y+1)-1;
while(l<=r){
int mid=l+r>>1;
if(cal(x,x+mid-1)==cal(y,y+mid-1)) l=mid+1;
else r=mid-1;
}return l-1;
}
inline void ins(int xx,int val){//在第xx个之前插入val
int x=find(rt,xx-1),y=find(rt,xx);
splay(x,rt);splay(y,c[x][1]);c[y][0]=++n;fa
=y;
v
=val;update(n);update(y);update(x);
}
int main(){
//  freopen("a.in","r",stdin);
scanf("%s",s+1);n=strlen(s+1)+2;bin[0]=1;
for(int i=1;i<=50300;++i) bin[i]=bin[i-1]*k1;
build(rt,1,n);m=read();
while(m--){
char op[5];scanf("%s",op+1);
if(op[1]=='Q'){
int x=read()+1,y=read()+1;
splay(x,rt);x=sz[c[x][0]]+1;
splay(y,rt);y=sz[c[y][0]]+1;
printf("%d\n",lcp(x,y));continue;
}scanf("%s",op+1);int x=read();
if(x>n-2) x=n-1;ins(x+1,op[1]);
}return 0;
}