Compilare: user.c: In function 'scan': user.c:18: warning: format '%d' expects type 'int *', but argument 2 has type 'char *' user.c: In function 'solve_b': user.c:107: warning: array subscript has type 'char' user.c:107: warning: array subscript has type 'char' user.c: In function 'main': user.c:115: warning: control reaches end of non-void function