Kotlin Sum of positive number

Support
1

Our task is to find in Kotline Sum of positive number in defined function. We written below code but getting compilation error. Hence need expertise advice for it -

import java.io.*
import java.math.*
import java.security.*
import java.text.*
import java.util.*
import java.util.concurrent.*
import java.util.function.*
import java.util.regex.*
import java.util.stream.*
import kotlin.collections.*
import kotlin.comparisons.*
import kotlin.io.*
import kotlin.jvm.*
import kotlin.jvm.functions.*
import kotlin.jvm.internal.*
import kotlin.ranges.*
import kotlin.sequences.*
import kotlin.text.*

fun sum(nums:Array<Int>,add: (acc:Int,ele:Int) -> Int):Int {
      var res=0
    for(i in nums){
        res = add(res,i)
    }
    return res
}

--Editable Code---
fun getLambda(): (acc:Int,ele:Int) -> Int {
    var lambda = { acc: Int, ele: Int -> acc + ele }
    return lambda
}
---END--

fun main(args: Array<String>) {
    val numsCount = readLine()!!.trim().toInt()

    val nums = Array<Int>(numsCount, { 0 })
    for (i in 0 until numsCount) {
        val numsItem = readLine()!!.trim().toInt()
        nums[i] = numsItem
    }
    
    val lambda = getLambda()
    val result = sum(nums,lambda)
    println(result)
}
2

Maybe you should tell us what is the compilation error you get.

3

I can find any compilation error in your code:

fun sum(nums: Array<Int>, add: (acc: Int, ele: Int) -> Int): Int {
    var res = 0
    for (i in nums) {
        res = add(res, i)
    }
    return res
}

//sampleStart
fun getLambda(): (acc: Int, ele: Int) -> Int {
    var lambda = { acc: Int, ele: Int -> acc + ele }
    return lambda
}
//sampleEnd

fun main() {
    val nums = arrayOf(1,2,3,4,5) // Simplified to run in the playground

    val lambda = getLambda()
    val result = sum(nums, lambda)
    println(result)
}
4

yes but now it is fine but desire output not coming.

Our task is

Write a lambda expression that can be used to find the sum of positive numbers in the defined function sum.

var lambda = in this seems we need to call sum function

5

can we try with

var lambda = sum(acc, ele)

6

I’m guessing that you are only supposed to sum positive numbers. That means that you need to check if ele is greater than 0 before adding it.

This sounds like homework so I’ll let you figure out the exact code :wink:

1 Like
7

any suggestion

8

As I said I won’t do your homework. What did you change based on my comment?

How do you know that. Do you have an example with the correct result? What is the error you get?
It’s really hard to help you unless you give us some more information.

1 Like
9

You need to check for negative integer condition while calculating the sum

for(i in nums){
   if(i>0)  //this is the base condition
    res = add(res,i)
}
10

Your solution:
fun sum(nums:Array,add: (acc:Int,ele:Int) → Int):Int {
var res=0
var newNumsArr= nums.filter{ it > 0 }
for(i in newNumsArr){
res = add(res,i)
}
return res
}
fun getLambda(): (acc:Int,ele:Int) → Int {
var lambda = {x:Int,y:Int → x +y}
return lambda
}

11

fun sum(nums:Array,add: (acc:Int,ele:Int) → Int):Int {
var res=0
var num= nums.filter{ it > 0 }
for(i in num){
res = add(res,i)
}
return res
}

fun getLambda(): (acc:Int, ele:Int) → Int {
var lambda= { acc:Int, ele:Int → acc + ele }
return lambda
}

fun main() {
val numsCount = readLine()!!.trim().toInt()

val nums = Array<Int>(numsCount, { 0 })
for (i in 0 until numsCount) {
    val numsItem = readLine()!!.trim().toInt()
    nums[i] = numsItem
}

val lambda = getLambda()
val result = sum(nums,lambda)
println(result)

}
here bro this is 100 percent working, all 4 test cases successfully passed.