both code did same.what is the difference? ~~~~~ First one : set s; s.insert (1);s.insert (3);s.insert (5); auto tr = s.lower_bound (2);

s.erase (tr);<-----------here

Second one : set s; s.insert (1);s.insert (3);s.insert (5); auto tr = s.lower_bound (2); s.erase (*tr);<-----------here ~~~~~