Compilare: user.cpp: In function 'int getNumber()': user.cpp:43: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'int eval()': user.cpp:51: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'int main()': user.cpp:112: warning: unused variable 'i' user.cpp:112: warning: unused variable 'j' user.cpp:112: warning: unused variable 'k' user.cpp: In function 'int simply(int, int, char)': user.cpp:31: warning: control reaches end of non-void function