Kotlin Basic Programs for Beginners

What is the output of the following Kotlin code?

fun main() {
val num1: Int? = null
val num2: Int = 5
println(num1 ?: num2)
}

What is the output of the following Kotlin code?

fun main() {
val num1 = 10
val num2 = 20
val result = if (num1 > num2) "num1 is greater than num2" else "num2 is greater than num1"
println(result)
}

What is the output of the following Kotlin code?

fun main() {
val arr = arrayOf(1, 2, 3, 4, 5)
for (i in arr.indices step 2) {
println(arr[i])
}
}

What is the output of the following Kotlin code?

fun main() {
var i = 0
while (i < 5) {
println("Hello, world!")
i++
}
}

What is the output of the following Kotlin code?

fun main() {
val name: String? = null
println(name?.length ?: -1)
}