Compilare: user.cpp: In member function ‘int Mare::zero()’: user.cpp:234:35: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] return A[0] == 0 || A[0] == 1 && A[1] == 0 ; ^ user.cpp: In member function ‘void Mare::radical_normal(Mare&, int)’: user.cpp:440:59: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if ( !C.zero () || i == 3 + ( X[0] % 2 == 0 ) && AUX ) { ^ user.cpp: In function ‘int main()’: user.cpp:549:27: warning: converting to non-pointer type ‘char’ from NULL [-Wconversion-null] tmp2[cnt - 1] = NULL; ^ /tmp/ccbeoH5h.o: In function `main': user.cpp:(.text.startup+0x95): warning: the `gets' function is dangerous and should not be used.