Compilare: user.cpp: In function 'void DF(long int)': user.cpp:25: warning: comparison between signed and unsigned integer expressions user.cpp: In function 'void REC(long int)': user.cpp:49: warning: comparison between signed and unsigned integer expressions user.cpp:52: warning: format '%c' expects type 'int', but argument 2 has type 'long int' user.cpp: In function 'int main()': user.cpp:77: warning: array subscript has type 'char' user.cpp:77: warning: array subscript has type 'char'