Operator Precedence in Java, I can't find out the result

Question

Can someone explain to me why the result is 30?

System.out.println(30 - 12 / (2*5) +1);

Answer 1

This is simple arithmetic order of operations. 30 - 12 / (2 * 5) + 1 breaks down thus:

• Work the parentheses first: 2 * 5 becomes 10. You now have 30 - 12 / 10 + 1.
• Division takes precedence over all other present operators, so you're dividing 12/10 as integers, so you'll get 1 as the quotient. You now have 30 - 1 + 1.
• You then subtract 30 from 1, then add 1 back to get 30.