Compilare: user.cpp: In function ‘bool bf()’: user.cpp:32: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:80: warning: array subscript has type ‘char’ user.cpp:82: warning: array subscript has type ‘char’ user.cpp:85: warning: array subscript has type ‘char’ user.cpp:124: warning: array subscript has type ‘char’ user.cpp:125: warning: array subscript has type ‘char’