[Error] 'nullptr' was not declared in this scope.
if in red_black_tree program, this error occurs,then change language standard (-std) to ISO C++11 in the compiler settings.
[Error] 'nullptr' was not declared in this scope. if in red_black_tree program, this error occurs,then change language standard (-std) to ISO C++11 in the compiler settings.
C++GPL-3.0