Kotlin Newbie To Pro - VARARG, DEFAULT AND NAMED PARAMETERS - Part 18

[@PB-op3tk]

Hi, i think there is a little mistake in the solution (14:20). In line 14, shouldn't it be: for (i in 0 until list.size), because until does not include the last number, so if you would search for 7 it would return -1 However, nice videos, thanks! 👍

[@PB-op3tk]

Okay, I just saw that someone mentioned the problem in the next video.. so, that applies here, too :)

[@veeecos]

+1

[@luismarez4792]

first homework i share: fun alternatingSum(vararg numbers: Int) : Int { var n: Int = 1 var sum: Int = 0 for(item in numbers) { sum += (item * n) n *= -1 } return sum } and thank you for your tutorials they really help me

[@willianrodrigohuber7968]

Thanks for this video, my answer for the homework stay bellow fun main() { val sum = alternatingSum(3, 4, 5, 2, 1, 2, 3) println("The alternating sum is $sum") } fun alternatingSum(vararg values: Int): Int { var sum = 0 for (index in values.indices) { if (index % 2 == 0) sum += values[index] else sum -= values[index] } return sum }

[@younesscoder]

Thanks again dude =>This is the solution of the Homework fun main() { val sum = alternatingSum(3, 4, 5, 2, 1, 2, 3) println("The alternating sum is $sum") } fun alternatingSum(vararg numbers: Int): Int { var result = numbers[0] var o = 0 while(o != (numbers.size - 1)) { o++ result -= numbers[o] o++ result += numbers[o] } return result }

[@VijayRaj-pw2px]

fun main() { // create function that will take a vararg list of numbers and return an alternating sum val num = alternatingSum(2, 4, 8, 10, 14) println("The alternating sum is $num") } fun alternatingSum(vararg numbers: Int): Int { var total = 0 for(i in 0 until numbers.size step 2) { total += numbers[i] } for(i in 1 until numbers.size step 2) { total -= numbers[i] } return total }

[@opdmin]

fun main() { val sum = alternatingSum(16,64,47,2,9,18,3,1,74) println("The alternating sum is $sum") } fun alternatingSum(vararg numbers: Int): Int { var sum = 0 val numberTotal = numbers.size - 1 for(i in 0.. numberTotal) { if(i%2 != 0) { // odd indexes sum -= numbers[i] // subtract value } else { // positive indexes (includes index 0) sum += numbers[i] // add value } } return sum }

[@swakshatmishra]

fun alternatingSum(vararg numbers: Int): Int { var sum = numbers[0] for(i in 1..

[@aakashkumaryadav6048]

//HomeWork : fun main() { val result = alternatingSum(3, 4, 5, 2, 1, 2, 3) println("The alternating sum is: $result") } fun alternatingSum(vararg numbers: Int): Int { var evenSum = 0 var oddSum = 0 for(i in numbers.indices) { if(numbers[i]%2 == 0) { evenSum += numbers[i] } else { oddSum += numbers[i] } } return oddSum - evenSum } //Thankk you sir

[@ekkawutemeelugsana7068]

fun main() { val sum = alternatingSum(3,4,5,2,1,2,3) println("The alternating sum is $sum") } fun alternatingSum(vararg numbers : Int) : Int { var result = 0 for((index,item) in numbers.withIndex()) if (index % 2 == 0) result += item else result -= item return result }

[@Macias096]

Is it okay to use, in for loop, the indices function instead of 0 until list.size-1? Looks like this: for (i in list.indices). Program works fine with that.

[@paulvickers8059]

fun main() { val sum = alternatingSum(3, 4, 5, 2, 1, 2, 3) println("The alternating sum is $sum") } fun alternatingSum(vararg numbers: Int): Int { var result = numbers[0] for (i in 1 until numbers.size) { if (i % 2 == 0) result += numbers[i] else result -= numbers[i] } return result }

[@PandleHandle]

What does the asterisk in *array do? Are there any other uses for it?

[@PandleHandle]

The * operator is known as the Spread Operator in Kotlin. When we call a vararg-function, we can pass arguments one-by-one, e.g. asList(1, 2, 3), or, if we already have an array and want to pass its contents to the function, we use the spread operator (prefix the array with *):

[@soualehmohamedaya6625]

Homework : fun alternatingSum(vararg numbers: Int) : Int { var sum = 0 var x = 0 for ( i in numbers ) { if ( x == 0 ) { sum += i x = 1 } else { sum -= i x = 0 } } return sum } fun main() { println(alternatingSum(1,2,3,4,5,6)) }

[@TheImaginativeSachin]

interesting

[@itamarribeiro8865]

fun alternatingSum(vararg values: Int) { var result = 0 var sum = true for (i in values) { if (sum) result += i else result -= i sum = !sum } println("The alternating sum is $result") }

[@MrSarma1991]

my homework :D fun alternatingSum(vararg niz: Int):Int { var plusminus=0 var rezultat=0 for(i in niz) { if (plusminus==0) { rezultat += i plusminus = 1 }else { rezultat -= i plusminus = 0 } } return rezultat }

[@AniobiStanley]

fun alternatingSum(vararg numbers: Int): Int{ var sum = 0 for (i in numbers.indices){ if (i % 2 == 0) sum += numbers[i] else sum -= numbers[i] } return sum }

[@alh311]

Homework: fun alternatingSum(vararg numbers: Int): Int { var sum = 0 var signModifier = 1 for (number in numbers) { sum += (signModifier * number) signModifier *= -1 } return sum }

[@shakibhasan858]

a little mistake in line number 14. in the for loop the until keyword don't include the last number. So it should be list.indices

[@Jonathan1Brito]

fun main() { sumValue(1, 5) } fun sumValue(a:Int, b:Int){ var count = a var res = 0 while (count

[@pranaydas3320]

fun main() { val sum = alternatingSum(3, 4, 5, 2, 1, 2, 3, 20,12, 4, 6,7,9,34) println("The alternating sum is $sum") } fun alternatingSum(vararg numbers: Int): Int { var altSum = 0 for (i in numbers.indices) { if (i%2 == 0){ altSum += numbers[i] } else { altSum += numbers[i] * -1 } } return altSum }

[@Twishma]

fun main() { val sum = alternatingSum(3,4,5,2,1,2,3) println("The alternating sum is $sum") } fun alternatingSum(vararg numbers: Int): Int { var sum = 0 for(i in 0 until numbers.size) { if(i % 2 == 0){ sum += numbers[i] }else{ sum -= numbers[i] } } return sum }

[@jonievillejo6746]

fun main() { println("For this list [3, 4, 5, 2, 1, 2, 3]") println("The alternating sum is: ${alternatingSum(3, 4, 5, 2, 1, 2, 3)}") } fun alternatingSum(vararg numbers: Int): Int { var theSum = 0 for ( elementValue in numbers ) { theSum *= -1 theSum += elementValue } return theSum }

[@LtMewS]

I Used boolean flag variable for this problem fun alternateSum(vararg numbers: Int): Int{ var flag = true var sum = 0 for(i in numbers){ if (flag){ sum+=i flag=false } else{ sum-=i flag=true } } return sum }

[@callmejacrispy]

fun main() { val sum = altSum(3, 4, 5, 2, 1, 2, 3) println(sum) // Output should be 0 } fun altSum(vararg numbers: Int): Int { var sum = 0 for (i in numbers.indices) { if (i % 2 == 0) { sum += numbers[i] // Add numbers at even index positions } else { sum -= numbers[i] // Subtract numbers at odd index positions } } return sum }

[@feanor2718]

I'm Confused:Take a look at the junk i've written: fun alternatingSum(vararg number: Int): Int { var value: Int = number[0] for (i in number.indices) { if (i != number.size - 1) { when { i % 2 == 0 -> value -= number[i + 1] else -> value += number[i + 1] } } } return value }

[@lifesurprise9313]

lists and arrays is a very difficult subject, they make ne so confused

[@bogite8734]

fun main() { val sum = alternatingSum(3, 4, 5, 2, 1, 2, 3) println("The alternating sum is $sum") } fun alternatingSum(vararg numbers:Int):Int { var current_symbol = "+" var result = 0 for(n in 0..numbers.size-1) { val number = numbers[n] if(current_symbol == "+") { result += number current_symbol = "-" } else if (current_symbol == "-") { result -= number current_symbol = "+" } } return result }

[@mkc0321]

amazing

[@MrJonas04]

Who watches this in 2020?

[@SerhiiOr]

I

[@MrJonas04]

@@SerhiiOr ok

[@jessajanson1344]

2021 !!

[@LtMewS]

2023

[@younesscoder]

2023 :^)

[@DeathlabelCSS]

fun main() { val sum = alternatingSum(3,4,5,2,1,2,3) println("The alternating sum is $sum") } fun alternatingSum(vararg list: Int): Int{ var sum = list[0] for (i in 1..list.size - 1){ if(i % 2 == 0) // for those that dont know this mathmatical equation its called MOD and essentially it says i divided by 2, but returns the remainer so i MOD 2 would = 0 for even numbers sum += list[i] else sum -= list[i] } return sum }

[@roymustang7031]

//my solution for the homework fun main(){ var myNumbers=newp(3,4,5,2,1,2,3) println("The sum is $myNumbers") } fun newp(vararg numbers: Int): Int{ var result=numbers[0] for(i in 1..numbers.size-1){ if(i%2==0){ result+=numbers[i] } else{ result-=numbers[i] } } return result }

[@Kids____Zone]

who watches in 2022?

[@ekafrancium]

fun main() { val list = listOf(1,2,3,4,5,6,7) println(list) println("Search for a number in the $list: ") val z = readlnOrNull()?.toInt() if(z!=null) { println("The index of the $z is: ${indexof(list, z)}") } } fun indexof(list: List, value: Int): Int{ for (i in 0 ..list.size){ if(list[i]==value){ return i } } return -1 }