for loop in kotlin up by 2 code example

Example 1: for loop kotlin

val array = arrayOf(1, 3, 9)
for (item in array) {
    //loops items
}
for (index in 0..array.size - 1) {
	//loops all indices
}
for (index in 0 untill array.size) {
    //loops all indices
}
for (index in array.indices) {
    //loops all indices (performs just as well as two examples above)
}

Example 2: kotlin loop

var bubbles = 0
while (bubbles < 50) {
    bubbles++
}
println("$bubbles bubbles in the water\n")

do {
    bubbles--
} while (bubbles > 50)
println("$bubbles bubbles in the water\n")

repeat(2) {
     println("A fish is swimming")
}
-> 50 bubbles in the water
49 bubbles in the water
A fish is swimmingA fish is swimming