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Using the comma operator So operators will be covered later in this section.

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However, it's useful to introduce the comma operator here.

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So you can have a second set of expressions separated by a comma as a single statement.

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For example, let's create an example code here to show you how this comma operator works.

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Integer A equals nine, for example.

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Integer A equals nine.

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Integer B equals four.

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Integers.

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C equals nothing, so it's automatically zero.

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So let's see.

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Equals E two plus eight and comma operator B plus one.

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So as you can see here, we have a slight problem here.

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So this code compile and run without problem and the variable C will be assigned with the value of 17.

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Let's print it and I will show you what this is.

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C here.

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And std.

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STD endl here.

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So let's print this here.

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As you can see here, we got 11, so eight plus nine new plus nine, and we will get 11.

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But where is our five?

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So as you know, four plus one equals.

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Equals five.

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So here.

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17.

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And.

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Uh, 17 and five.

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As you can see here, this 17 and five did not multiply.

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So that's because of the the comma operator is not to multiply here.

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So I will explain what this comma is.

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So the reason is that this is the reason that the comma operator.

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Separates the right side of the assignment into two expressions.

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Plus one and B plus a, A plus eight and B plus one.

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And it uses the value of the first expression to assign C later in this course, we will look at the

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operator precedence.

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However, it's worth saying here that the comma has the lowest precedence and plus has higher precedence

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than equal to sign here.

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So the statement is executed in order of the addition to the addition of of the addition.

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So the assignment and then the comma operator with the result of B plus one thrown away just as earlier

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as you can see we just get 17 from C here so you can change the precedence using the parentheses to

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group expressions.

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For example, let's.

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I mistyped called could have been here as follows.

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Let's get into the parentheses and see what happens here.

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As you can see here, we got the five.

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Now.

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And so the result is this statement is variable C assigned to five, B plus one.

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And where is our 17 here?

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So the reason is that with the comma operator expression are executed from the left to right.

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So the value of the group of expression is the type most one.

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So there are some cases, for example, in the initialization or loop expression for a for loop where

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you will find the comma operator useful.

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But as you can see here, even used intentionally, the comma operator produced hard to read code.

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So now actually.

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Let's end our.

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Lecture now and in the next lecture you will learn about your types and variables.