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In this video, we'll learn about c++'s compound assignment operators.

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These operators are very easy to use and commonly used in c++ code.

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The syntax for the operators is pretty simple.

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It's the operator you wish to use immediately followed by an equal sign.

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There are quite a few of these operators, but we'll focus on the mathematical operators.

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The bottom half of this table includes the operators that are used to manipulate bits.

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They're called bitwise operators. And I'll cover them later in this course.

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So let's look at the first one in the table. The plus equal operator.

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We apply the operator as in the example column.

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For example, left-hand side plus equals right-hand side.

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The meaning of this would be to increment the left-hand side

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by the right-hand side

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and then store the resulting value in the left-hand side.

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We'll see a few real code examples in the next slide.

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All of these operators work the same way.

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For example, the multiplication equal operator multiplies the left-hand side

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by the right-hand side and stores the product back in the left-hand side.

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Let's see some examples.

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Here we see some examples of using several of the compound assignment operators.

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Let's look at the first example. A plus equals one.

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This means increment the left-hand side by the right-hand side

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and store the result back into the left-hand side.

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So this is the same as a equals a plus one.

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And it's another way of incrementing a variable by one.

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The second example works exactly the same way except that we'll be dividing the

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a by 5., then storing the result back into a.

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The third example shows how the entire right-hand side is evaluated

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before the operator is applied.

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In this case, we have a multiplication equal

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b plus c.

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This means multiply a by the sum of b plus c.

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Then store the product back in a.

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In the last example, we're incrementing cost by the product of item and tax.

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The best tip I can give you when you write these operators is to think of the right-hand side

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as being inside parentheses and you'll always have it right.