Can anyone tell me why my arithmetic code isn't working?

Question

//ax + b = c
//x = (c-b)/a

fun main(args: Array<String>) {
var equ = readLine()!!.toString()
var a: Int = equ.get(0).toInt()
var b: Double = equ.get(3).toDouble()
var c: Double = equ.get(5).toDouble()

println("X is equal to ${(c - b) / a}")

Answer 1

If you space separate your input, you could make a list of them. Data entered to prompt:
3 2.1 4.5

val equ = readLine()!!.split(" ")
makes equ a listOf("3", "2.1", "4.5")

val a = equ[0].toInt()
val b = equ[1].toDouble()
val c = equ[2].toDouble()
gets the numbers from the strings.

Since you are not modifying your variables, they should be declared val instead of var.

Answer 2

In kotlin, when converting Char to Int (using toInt()), the, the character value is returned, not the number it represents... So for 1, this would be 49...
You could first convert your char to string, and then go on converting to Int... This would meet your expectation...

equ.get(0).toString().toInt()...

Further, I think you want to access index 0, 2, 4... Not 0, 3, 5 ??

Answer 3

Thank you so much!

Answer 4

Obviously the goInt() and toDouble() functions work different from your (and my) expectations, but I'm not familiar with Kotlin, so I can't help you. But maybe this hint helps you to find the proper solution...