ecuatii.cpp: In function `int main()': ecuatii.cpp:25: warning: assignment to non-pointer type `char' from NULL ecuatii.cpp:25: warning: argument to non-pointer type `char' from NULL ecuatii.cpp:29: warning: assignment to `int' from `double' ecuatii.cpp:29: warning: argument to `int' from `double' ecuatii.cpp:35: warning: comparison between signed and unsigned integer expressions ecuatii.cpp:65: warning: comparison between signed and unsigned integer expressions