contains

import kotlin.test.*

fun main() { 
   //sampleStart 
   val string = "Kotlin 2.2.0"
println("\"K\" in string is ${"K" in string}") // true

// The string only contains capital K
println("\"k\" in string is ${"k" in string}") // false
// However, it will be located if the case is ignored
println("string.contains(\"k\", ignoreCase = true) is ${string.contains("k", ignoreCase = true)}") // true

// Every string contains an empty string
println("\"\" in string is ${"" in string}") // true
// The string contains itself ...
println("string in string is ${string in string}") // true
// ... even if it is empty
println("\"\" in \"\" is ${"" in ""}") // true

// String's prefix is shorter than a string, so it can't contain it
println("string in \"Kotlin\" is ${string in "Kotlin"}") // false 
   //sampleEnd
}