int month , year, day,
month = sc.nextInt();
yeat = sc.nextInt();
day = sc.nextInt();
just like that. then how can i compute those inputted by the user.
In case of stones using if-else here is not the best solution. They are dependent on months only afaik. I would make an array and fill the array with the names of stones. Then you just need to print out stonesArray[month-1] and you will get the answer.
In case of zodiac it seems to be more complicated, as it is determined based on exact days. Perhaps, if-else is suitable here. Using if-else conditions you'll need to check the input date 12 times e.g.
if ((month == 1 && day >= 20) || (month == 2 && day <= 18)) //output Aquarius
else if ((month == 2 && day >= 19) || (month == 3 && day <= 20)) // output Pisces
else if ...
else // output Capricorn