Answer 1

Here we go!

https://code.sololearn.com/cVb3jtC4j0hB/?ref=app

Answer 2

for this kind of task, the do ... while loop could be a good solution:

fun main(args: Array<String>) {
var count = 0
do{
var num = readLine()!!.toInt()
count++
} while (num != 0)
println(count - 1)
}

Answer 3

fun main(args: Array<String>) {

var i= 0
while(true) {
var input = readLine()!!.toInt()

i++

if(input==0) break

}
println(i-1)
}

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I hope this code helped!