Math Operators

Java provides 5 math operators as listed below:

• + Addition, as well as unary +
• - Subtraction, as well as unary -
• * Multiplication
• / Floating point and integer division
• % Modulus, remainder of integer or floating point division

The numerical result and data type of the answer depends on the type of operands used in a problem.

For all the operators, if both operands are integers, the result is an integer. Examples:

• 2 + 3 -> 5
• 9 - 3 -> 6
• 4 * 8 -> 32
• 11/2 -> 5

Notice that 11/2 is 5, and not 5.5. This is because ints work only with whole numbers. The remaining half is lost in integer division.

If either of the operands is a double type, the result is a double type. Examples:

• 2 + 3.000 -> 5.000
• 25 / 6.75 -> 3.7037
• 11.0 / 2.0 -> 5.5

When an integer and a double are used in a binary math expression, the integer is promoted to a double value, and then the math is executed. In the example 2 + 3.000 -> 5.000, the integer value 2 is promoted to a double (2.000) and then added to the 3.000.

The modulus operator (%) returns the remainder of dividing the first operand by the second. For example:

• 10 % 3 -> 1
• 2 % 4 -> 2
• 16 % 2 -> 0
• 27.475 % 7.22 -> 5.815

Changing the sign of a value can be accomplished with the negation operator (-), often called the unary (-) operator. A unary operator works with only one value. Applying the negation operator to an integer returns an integer, while applying it to a double returns a double value. For example:

• -(67) -> -67
• -(-2.345) -> 2.345

To obtain the answer of 5.5 to a question like 11/2, we must cast one of the operands.

• (double)11/2 results in 5.5

The casting operators are unary operators with the following syntax:

• (type) operand

The same effect can also result from simply

• 11.0/2