EULER-SR throws error NULL was not declared in this scope

Question

[rohitsatyam102]

Hi Everyone.

I obtained the EULER-SR assembly tool and I was trying to install it. However to throws the following error.

cd  assembly && gmake
gmake[1]: Entering directory /home/demo/rohit/eulersr/euler-sr.1.1.2/assembly'
Makefile:86: /home/demo/rohit/eulersr/euler-sr.1.1.2/assembly/make.dep: No such file or directory 
114 files found.
gmake[1]: Leaving directory /home/demo/rohit/eulersr/euler-sr.1.1.2/assembly'
gmake[1]: Entering directory /home/demo/rohit/eulersr/euler-sr.1.1.2/assembly'
g++ -c -O3 -DNDEBUG  -I/home/demo/rohit/eulersr/euler-sr.1.1.2/lib  PathLib.cpp  -o x86_64/PathLib.o
g++ -c -O3 -DNDEBUG  -I/home/demo/rohit/eulersr/euler-sr.1.1.2/lib  PathBranch.cpp  -o x86_64/PathBranch.o
PathBranch.cpp: In function ‘void DeletePathTree(PathBranch&)’:
PathBranch.cpp:21:29: error: ‘NULL’ was not declared in this scope
  if ((*branchIt).second != NULL) {
                            ^
gmake[1]: *** [x86_64/PathBranch.o] Error 1
gmake[1]: Leaving directory /home/demo/rohit/eulersr/euler-sr.1.1.2/assembly'
gmake: *** [assembly] Error 2

Any help from C++ expert or others will be highly appreciated. The algo is available here