Compilare: user.c: In function 'valid': user.c:59: warning: unused variable 'tma' user.c: In function 'comb': user.c:74: warning: unused variable 'i' user.c: In function 'solve': user.c:112: warning: unused variable 'i' user.c:127:2: warning: no newline at end of file user.c: In function 'main': user.c:127: warning: control reaches end of non-void function /tmp/cc1vY8Qb.o: In function `scan': user.c:(.text+0x6be): warning: the `gets' function is dangerous and should not be used.