Hash_1014: [JSOI2008]火星人prefix

 #include <iostream>
 #include <cstdio>
 #include <cstring>
 #include <cmath>
 #include <algorithm>
 using namespace std;
 typedef unsigned int ll;
 #define maxn 150005
 #define p 53
 int n,m,root,tot,fa[maxn],son[maxn][],size[maxn];
 ll val[maxn],sum[maxn],bin[maxn];
 char st[maxn],op[];
 void read(int &x){
     x=; int f=; char ch;
     for (ch=getchar();!isdigit(ch);ch=getchar()) if (ch=='-') f=-;
     for (;isdigit(ch);ch=getchar()) x=x*+ch-''; x*=f;
 }
 struct SPLAY{
     int which(int x){
         return son[fa[x]][]==x;
     }
     void updata(int x){
         int ls=son[x][],rs=son[x][];
         size[x]=size[ls]+size[rs]+;
         sum[x]=sum[rs]+val[x]*bin[size[rs]]+sum[ls]*bin[+size[rs]];
     }
     int build(int l,int r){
         int x; if (l>r) return ; int mid=(l+r)>>;
         if (mid==) x=n+,val[x]=;
         else if (mid==n+) x=n+,val[x]=;
         else x=mid,val[x]=st[x]-'a'; size[x]=;
         son[x][]=build(l,mid-),son[x][]=build(mid+,r),updata(x);
         if (son[x][]) fa[son[x][]]=x;
         if (son[x][]) fa[son[x][]]=x;
         return x;
     }
     void rotata(int x){
         int y=fa[x],d=which(x),dd=which(y);
         if (fa[y]) son[fa[y]][dd]=x; fa[x]=fa[y];
         fa[son[x][d^]]=y,son[y][d]=son[x][d^];
         fa[y]=x,son[x][d^]=y,updata(y);
     }
     void splay(int x,int goal){
         while (fa[x]!=goal){
             if (fa[fa[x]]==goal) rotata(x);
             else if (which(x)==which(fa[x])) rotata(fa[x]),rotata(x);
             else rotata(x),rotata(x);
         }
         if (goal==) root=x; updata(x);
     }
     int kth(int x){
         int y=root,ls,rs; if (!root) return ;
         for (;;){
             ls=son[y][],rs=son[y][];
             if (size[ls]+==x) return y;
             else if (size[ls]>=x) y=ls;
             else x-=size[ls]+,y=rs;
         }
     }
     bool check(int x,int y,int len){
         int t1,t2; t1=kth(x),t2=kth(x+len+);
         ll z;splay(t1,),splay(t2,t1),z=sum[son[t2][]];
         t1=kth(y),t2=kth(y+len+); splay(t1,),splay(t2,t1);
         return z==sum[son[t2][]];
     }
 }Splay;
 void query(int x,int y){
     int l=,r,mid,ans=; r=min(tot--x+,tot--y+);
     while (l<=r){
         mid=(l+r)>>;
         if (Splay.check(x,y,mid)==) ans=mid,l=mid+;
         else r=mid-;
     }printf("%d\n",ans);
 }
 int main(){
     bin[]=; for (int i=;i<=;i++) bin[i]=bin[i-]*p;
     scanf("%s",st+),n=strlen(st+);
     root=Splay.build(,n+); tot=n+;
     read(m);
     for (int x,y;m;m--){
         scanf("%s",op+);
         if (op[]=='Q') read(x),read(y),query(x,y);
         else if (op[]=='R') read(x),scanf("%s",op+),x=Splay.kth(x+),Splay.splay(x,),val[x]=op[]-'a',Splay.updata(x);
         else{
             read(x),scanf("%s",op+),++tot,val[tot]=op[]-'a',size[tot]=;
             int t1=Splay.kth(x+),t2=Splay.kth(x+); Splay.splay(t1,),Splay.splay(t2,t1);
             fa[tot]=t2,son[t2][]=tot,Splay.updata(t2),Splay.splay(tot,);
         }
     }
     return ;
 }

Splay维护，询问时二分答案，Hash判定，我用的是53进制。

splay，二分，Hash。