Loops (while statements)

In this lesson you will learn to repeat work with a while statement in Kotlin and how to tell it apart from a for statement. This is for anyone searching for "Kotlin while loop how to use".

A while statement repeats as long as its condition holds. The rule of thumb is to use a for statement when you already know the stopping point and a while statement when you do not.

The sample code initialises var i = 1, repeats while i <= 5, and increases the value by one with i++ inside the loop. You can see the loop exit at the moment the condition becomes false.

A common stumbling block for beginners is forgetting to update the variable the condition depends on. Miss that update and you get an infinite loop. Note too that a variable used this way has to be declared with var.

In real-world development, while statements are common where the number of repetitions is not known in advance - work that repeats until a condition is met.

📖 Reference code

fun main() {
    var i = 1
    while (i <= 5) {
        println("Pass ${i}")
        i++
    }
}

✍️ Your code

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