Compilare: user.cpp: In function ‘int main()’: user.cpp:15: warning: comparison between signed and unsigned integer expressions user.cpp:17: warning: array subscript has type ‘char’ user.cpp:17: warning: array subscript has type ‘char’ user.cpp:18: warning: array subscript has type ‘char’ user.cpp:18: warning: array subscript has type ‘char’ user.cpp:12: warning: ‘aux’ may be used uninitialized in this function