Compilare: user.c:6: warning: type defaults to 'int' in declaration of 'd1' user.c:7: warning: data definition has no type or storage class user.c:7: warning: type defaults to 'int' in declaration of 'd2' user.c: In function 'afisare': user.c:22: warning: unused variable 'j' user.c:22: warning: unused variable 'i' user.c: In function 'back': user.c:30: warning: unused variable 'j' user.c:72:2: warning: no newline at end of file user.c: In function 'solve': user.c:54: warning: 'x1' may be used uninitialized in this function user.c:54: warning: 'y1' may be used uninitialized in this function