Rope_(data_structure) | Wikipedia
A simple rope implementation in C++ ( with <cstring> but w\ concatenation(?) ) | codeforces
Немного про дерамиду по неявному ключу | codeforces
Fast I/O in C++ | GeekForGeeks
Implementing the Rope data structure using binary search trees (splay trees) | StackOverflow
C++ STL Ropes | GeekForGeeks
Rope<T,Alloc> docs
Rope implementations overview
Treap (дерамида) | Ideone
Rope on ITMO wiki
Treap with implicit key impl
My Rope Ideone
Treap explanation Youtube