77TAHKV4VZ4SWZZBEND24Y6BL7JLRXPYO33CA5FRH53WXEWSWS4QC
// modified in the last step is the one on the left of
// the entry, move back one step before inserting the
// split key/value.
// modified in the last step is the one on the right
// of the current entry, move right one step before
// inserting the split key/value.