Nullptr Not Declared In Scope Dev C++

Hi
I am a beginner and currently I am working on a program.
I have a main class called 'FenPrincipale' of daughter classes 'FenCene' and 'FenCenep'.

Mar 08, 2017  Migrating from C to C: NULL vs nullptr. Updated: 20191014. On my last project, my team started working on implementing object-oriented concepts in C. Eventually we realized that we were reimplementing multiple C features. We admitted to ourselves that we would not implement our constructs more efficiently than the C compiler.

My IDE sends me the following error at fencen.h and fencenep.h

'nullptr was not declared in the scope'
'identify 'nullptr' is a keyword in C ++ [-wc ++ 0x-compat]

The notification is the same in the headers of the two classes.

Here is the code of fencene.h

Here is the code of fencenep.h

Here is the code of fenprincipale.h

What can I do to fix the problem?

Nullptr Not Declared In Scope Dev C 2018

Thank you in advance....

Not Declared In Scope Arduino

1. $ g++ -v
2. COLLECT_GCC=c:Usersnikhil bhardwajmingw64bing++.exe
3. COLLECT_LTO_WRAPPER=c:/users/nikhil bhardwaj/mingw64/bin/../libexec/gcc/x86_64-w
4. Target: x86_64-w64-mingw32
5. Configured with: /home/drangon/work/mingw-w64-dgn/source/gcc/configure --host=x8
6. 6_64-w64-mingw32 --target=x86_64-w64-mingw32 --disable-nls --enable-languages=c,
7. c++,objc,obj-c++ --with-gmp=/home/drangon/work/mingw-w64-dgn/build/for_target --
8. enable-twoprocess --disable-libstdcxx-pch --disable-win32-registry --prefix=/hom
9. e/drangon/work/mingw-w64-dgn/target --with-sysroot=/home/drangon/work/mingw-w64-
10. Thread model: win32
11. struct node
12. int data;
13. };
14. {
15. node->data = data;
16. node->right = NULL;
17. }
18. $ g++ -I../includes bst.cpp
19. bst.cpp:13:18: error: 'nullptr' was not declared in this sc
20. bst.cpp:14:19: error: 'NULL' was not declared in this scope
21. g++ -std=c++11 -I../includes bst.cpp