One of n lines in a file: Difference between revisions

</pre>

=={{header|Kotlin}}==

<lang scala>// version 1.1.51

import java.util.Random

val r = Random()

fun oneOfN(n: Int): Int {

var choice = 1

for (i in 2..n) {

if (r.nextDouble() < 1.0 / i) choice = i

}

return choice

}

fun main(args: Array<String>) {

val n = 10

val freqs = IntArray(n)

val reps = 1_000_000

repeat(reps) {

val num = oneOfN(n)

freqs[num - 1]++

}

for (i in 1..n) println("Line ${"%-2d".format(i)} = ${freqs[i - 1]}")

}</lang>

Sample output:

<pre>

Line 1 = 100363

Line 2 = 99669

Line 3 = 100247

Line 4 = 100248

Line 5 = 100401

Line 6 = 99457

Line 7 = 100015

Line 8 = 100215

Line 9 = 99920

Line 10 = 99465