Compilare: user.cpp: In function ‘void draw()’: user.cpp:32:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<Vnodes.size();i++) ^ user.cpp: In function ‘void heap()’: user.cpp:41:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<Vnodes.size(); i++) ^ user.cpp:48:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<Vnodes.size(); i++) ^ user.cpp: In function ‘int main()’: user.cpp:138:14: warning: variable ‘volt’ set but not used [-Wunused-but-set-variable] bool volt[n]; ^ user.cpp:128:29: warning: ‘index’ may be used uninitialized in this function [-Wmaybe-uninitialized] of << fields[index].range; ^