浅谈 rope

#include <ext/rope>
using namespace __gnu_cxx;  

crope a,b;

#include<bits/stdc++.h>
#define Tp template<typename Ty>
#define Ts template<typename Ty,typename... Ar>
#define W while
#define I inline
#define RI register int
#define LL long long
#define Cn const
#define CI Cn int&
#define gc getchar
#define D isdigit(c=gc())
#define pc(c) putchar((c))
#include <ext/rope>
using namespace __gnu_cxx;  
using namespace std;
namespace Debug{
    Tp I void _debug(Cn char* f,Ty t){cerr<<f<<'='<<t<<endl;}
    Ts I void _debug(Cn char* f,Ty x,Ar... y){W(*f!=',') cerr<<*f++;cerr<<'='<<x<<",";_debug(f+1,y...);}
    Tp ostream& operator<<(ostream& os,Cn vector<Ty>& V){os<<"[";for(Cn auto& vv:V) os<<vv<<",";os<<"]";return os;}
    #define gdb(...) _debug(#__VA_ARGS__,__VA_ARGS__)
}using namespace Debug;
namespace FastIO{
    Tp I void read(Ty& x){char c;int f=1;x=0;W(!D) f=c^'-'?1:-1;W(x=(x<<3)+(x<<1)+(c&15),D);x*=f;}
    Ts I void read(Ty& x,Ar&... y){read(x),read(y...);}
    Tp I void write(Ty x){x<0&&(pc('-'),x=-x,0),x<10?(pc(x+'0'),0):(write(x/10),pc(x%10+'0'),0);}
    Tp I void writeln(Cn Ty& x){write(x),pc('\n');}
}using namespace FastIO;
Cn int N=5e4+10;
int m,L;
char str[N];
crope nw,s[N],t;
int main(){
    RI b=0,opt,p,v,c;read(m);W(m--) if(read(opt),opt==1) read(p),scanf("%s",&str),p-=b,nw.insert(p,str),s[++L]=nw;
    else if(opt==2) read(p,v),p-=b,v-=b,nw.erase(p-1,v),s[++L]=nw;
    else read(v,p,c),v-=b,p-=b,c-=b,t=s[v].substr(p-1,c),b+=count(t.begin(),t.end(),'c'),cout<<t<<'\n';return 0;
}