Hey I am working in kotlin. I want to know is there any way when we entering value we know which value is smallest in the list.

For example

var userInputList = mutableList<Boolean>()

User Input Number -> 5

userInputList -> false

Again User Input Number -> 2

userInputList -> false, true

Again User Input Number -> 7

userInputList -> false, true, false

Again User Input Number -> 1

userInputList -> false, false, false, true.

Main thing I want to know, which one is smallest number.

CodePudding user response：

val list = mutableListOf<Int>()

while (true) {
  val i = readln().toIntOrNull() ?: break
  list.add(i)
  val bools = list.fold(emptyList<Boolean>()) { acc, value ->
    acc   (value == list.minOrNull()!!)
  }
  println(list)
  println(bools)
}

This is an attempt to show the steps of fold:

Input:  5 2 7 1 3
Output: [false, false, false, true, false]

acc          value   to evaluate      evaluated       why is f ot t added?
[]           5       []   f           [f]             5 is not the minimum value
[f]          2       [f]   f          [f,f]           2 is not the minimum value
[f,f]        7       [f,f]   f        [f,f,f]         7 is not the minimum value
[f,f,f]      1       [f,f,f]   t      [f,f,f,t]       1 is the minimum value
[f,f,f,t,f]  3       [f,f,f,t]   f    [f,f,f,t,f]     4 is not the minimum value

CodePudding user response：

You can use the minOrNull function

val elements = mutableListOf<Int>()

fun main() {
    
    while(true) {
        print("Enter a number:")
        elements.add(
            readLine()?.toIntOrNull() ?: break
        )
        val smallestElement = elements.minOrNull()
        println("The smallest element in the list now is $smallestElement")
    }
    println("Bye bye!")
}