4.9. Assignment Operators

C++ provides several assignment operators for abbreviating assignment expressions. For example, the statement

can be abbreviated with the addition assignment operator += as

which adds the value of the expression on the operator’s right to the value of the variable on the operator’s left and stores the result in the left-side variable. Any statement of the form

in which the same variable appears on both sides of the assignment operator and operator is one of the binary operators +, -, *, /, or % (or a few others we’ll discuss later in the text), can be written in the form

Thus the assignment c += 3 adds 3 to c. Figure 4.13 shows the arithmetic assignment operators, sample expressions using these operators and explanations.

Fig. 4.13. Arithmetic assignment operators.