Compilare: user.cpp: In function ‘int main()’: user.cpp:18:32: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 0; i < strlen(a); ++ i){ ^ user.cpp:19:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] A[++ A[0]] = a[i]; ^ user.cpp:20:18: warning: array subscript has type ‘char’ [-Wchar-subscripts] A[++ A[0]] = '*'; ^ user.cpp:22:14: warning: array subscript has type ‘char’ [-Wchar-subscripts] A[++ A[0]] = '*'; ^ /tmp/ccjjrift.o: In function `main': user.cpp:(.text.startup+0x50): warning: the `gets' function is dangerous and should not be used.