Compilare: user.c: In function 'solve': user.c:11: warning: unused variable 't' user.c: In function 'read_data': user.c:75: warning: format '%s' expects type 'char *', but argument 2 has type 'char (*)[3000]' user.c:72: warning: unused variable 'k' user.c:72: warning: unused variable 'j' user.c: In function 'write_data': user.c:83: warning: unused variable 'i' user.c: In function 'solve': user.c:11: warning: 'poz' may be used uninitialized in this function