Your question: What is the difference between for and while loop in Javascript?

What is the difference between a for loop and a for in loop?

for loops are meant to iterate while incrementing/decrementing. for … in … loops are meant to enumerate through object properties.

What is while loop example?

A “While” Loop is used to repeat a specific block of code an unknown number of times, until a condition is met. For example, if we want to ask a user for a number between 1 and 10, we don’t know how many times the user may enter a larger number, so we keep asking “while the number is not between 1 and 10”.

Is a for loop or while loop faster?

Efficiency, and While vs For

Using for: % Time elapsed: 0.0010001659 seconds. Using while: % Time elapsed: 0.026000023 seconds. The main reason that While is much slower is because the while loop checks the condition after each iteration, so if you are going to write this code, just use a for loop instead.

What are the 3 types of loops?

Visual Basic has three main types of loops: for.. next loops, do loops and while loops.

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What is a for in loop?

A “For” Loop is used to repeat a specific block of code a known number of times. For example, if we want to check the grade of every student in the class, we loop from 1 to that number.

Can I put a while loop in a for loop?

All for loops can be written as while loops, and vice-versa. Just use whichever loop seems more appropriate to the task at hand. In general, you should use a for loop when you know how many times the loop should run.

What is the difference between while loop and do-while loop explain with example?

While the loop is an entry control loop because firstly, the condition is checked, then the loop’s body is executed. The do-while loop is an exit control loop because in this, first of all, the body of the loop is executed then the condition is checked true or false.

What do you mean by while loop?

A while loop is a control flow statement that allows code to be executed repeatedly based on a given Boolean condition. The while loop can be thought of as a repeating if statement.

How does a while loop start?

First, we set a variable before the loop starts (var i = 0;) Then, we define the condition for the loop to run. As long as the variable is less than the length of the array (which is 4), the loop will continue. Each time the loop executes, the variable is incremented by one (i++)

Does a for loop run at least once?

Since testing is done at the bottom of the loop, the loop body must execute at least once, regardless of conditions. Java does not “look ahead” to the condition that is tested. It executes the loop body, then tests the condition to see if it should execute it again.

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What are the pros and cons of for loop?

Pros: It’s straightforward. You loop through every single element for a given string or array . Cons: It’s very restricting, you can’t determine where to start or how long you want to go on for.

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