ecuatii.cpp: In function `int main()': ecuatii.cpp:32: warning: assignment to non-pointer type `char' from NULL ecuatii.cpp:32: warning: argument to non-pointer type `char' from NULL ecuatii.cpp:42: warning: assignment to non-pointer type `char' from NULL ecuatii.cpp:42: warning: argument to non-pointer type `char' from NULL ecuatii.cpp:77: warning: assignment to non-pointer type `char' from NULL ecuatii.cpp:77: warning: argument to non-pointer type `char' from NULL /tmp/ccQBfgUI.o(.text+0x4f): In function `main': : the `gets' function is dangerous and should not be used.