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Introduction to JavaScript

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Increment and Decrement Operators

Increment and Decrement are operations used to increase or decrease a variable's value by 1.

Increment

The increment operation is performed using the ++ operator:

let a = 0;
a++;
console.log(a);
a++;
console.log(a);
a++;
console.log(a);

              
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let a = 0;
a++;
console.log(a);
a++;
console.log(a);
a++;
console.log(a);
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Note

The expression a++ is equivalent to a = a + 1 or a += 1.

Decrement

The decrement operation is performed using the -- operator:

let a = 5;
a--;
console.log(a);
a--;
console.log(a);
a--;
console.log(a);

              
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let a = 5;
a--;
console.log(a);
a--;
console.log(a);
a--;
console.log(a);
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Note

The expression a-- is equivalent to a = a - 1 or a -= 1.

Increment and decrement operations are frequently used in loops, which we will discuss in more detail later.

question mark

Choose the correct result:

let a = 27;
a--;
a--;
a++;
a += 5;

Select the correct answer

Everything was clear?

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Thanks for your feedback!

Section 3. Chapter 4
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