These are +, *, -, and / for addition, multiplication, subtraction, and division. That's about it.
There is also the modulus operator, which looks like this: %. If you can't remember modulus, which actually comes in handy with surprising frequency, it is used to return the remainder of performing a division operation.
For example, 10 % 3 = 1, because 10 divided by 3 is 3 (which we don't care about) with a remainder of 1 (which is what we care about when we use modulus).
There's one more thing: you can use a special shorthand in combination with any of the arithmetic operators (excluding modulus) to modify an existing value.
Say you have a variable of type int called x and its value is 0, and you want to add 1 to it. You can ...