ecuatii.cpp: In function `void calculare(char*)': ecuatii.cpp:11: warning: comparison between signed and unsigned integer expressions ecuatii.cpp:16: warning: comparison between signed and unsigned integer expressions ecuatii.cpp:51: warning: comparison between signed and unsigned integer expressions ecuatii.cpp:74: warning: comparison between signed and unsigned integer expressions ecuatii.cpp:94: warning: comparison between signed and unsigned integer expressions ecuatii.cpp:117: warning: comparison between signed and unsigned integer expressions ecuatii.cpp: In function `int main()': ecuatii.cpp:149: warning: char format, different type arg (arg 2) ecuatii.cpp:151: warning: comparison between signed and unsigned integer expressions ecuatii.cpp:166: warning: assignment to non-pointer type `char' from NULL ecuatii.cpp:166: warning: argument to non-pointer type `char' from NULL ecuatii.cpp:167: warning: assignment to non-pointer type `char' from NULL ecuatii.cpp:167: warning: argument to non-pointer type `char' from NULL