Calculate project total min coast based on the bid amount given by developer for each project : Interview Question

Solution of code in Kotlin

    fun main() {
    val numOfProjects = 3
    val projectId = arrayOf(1, 2, 0, 1, 2, 0)
    val bids = arrayOf(35, 10, 8, 20, 25, 100)

    val cost = minCost(numOfProjects, projectId, bids)
    if (cost < 0) {
        println("No project assigned")
    } else {
        println("Min cost for All projects is $cost dollars")
    }
}

fun minCost(numOfProjects: Int, projectId: Array<Int>, bids: Array<Int>): Long {
    var cost = 0L
    // If project id don't contains all the the projects then return -1 or calculate min cost
    for (i in 0 until numOfProjects) {
        if (projectId.contains(i)) {
            cost = calculateMinCost(projectId, bids)
            break
        } else {
            return -1
        }
    }
    return cost
}

// Calculate min cost for all the project based on bid amount given by developer for each project
fun calculateMinCost(projectArray: Array<Int>, bidArray: Array<Int>): Long {
    val developerArray = ArrayList<DeveloperDetails>()

    // For assign unique key to each project and bid data

    val projectHashMap = HashMap<Int, Int>()
    val bidsHashMap = HashMap<Int, Int>()

    for (i in projectArray.indices) {
        projectHashMap[i] = projectArray[i]
    }

    for (i in bidArray.indices) {
        bidsHashMap[i] = bidArray[i]
    }

    for ((key, _) in bidsHashMap) {
        val projectId = projectHashMap.getValue(key)
        val bidAmount = bidsHashMap.getValue(key)

        // Store ProjectId and BidAmount to developer object
        developerArray.add(
            DeveloperDetails(
                projectId = projectId,
                bidAmount = bidAmount
            )
        )
    }
    // Sort developer data based on Project Id
    developerArray.sortBy { it.projectId }

    var minCost = 0
    // Compare each object with other to find out min bid amount of each Project and, add it's amount to minCoast and return it.
    for (i in 0 until developerArray.size) {
        for (j in i + 1 until developerArray.size) {
            if (developerArray[i].projectId == developerArray[j].projectId) {
                println("For Project ${developerArray[i].projectId} : Comparing bid amount of Dollar ${developerArray[i].bidAmount} with Dollar ${developerArray[j].bidAmount}")
                minCost += if (developerArray[i].bidAmount < developerArray[j].bidAmount) {
                    developerArray[i].bidAmount
                } else {
                    developerArray[j].bidAmount
                }
            }
        }
    }
    return minCost.toLong()
}

// For store project and bid amount details
data class DeveloperDetails(val projectId: Int, val bidAmount: Int)

Solution in Kotlin

Return -1 indicates no project assigned

fun getResult(numProjects: Int, arrProjectIds: Array<Int>, arrBids: Array<Int>): Long {
    return if (arrProjectIds.toSet().size != numProjects) {
        -1
    } else {

        // HashMap of ProjectID, Bid
        val hashMap = hashMapOf<Int, Int>()

        //Result
        var result: Long = 0L

        arrProjectIds.forEachIndexed { index, item ->
            val bid = arrBids[index]
            val bidAtProjectId = hashMap[item]
            if (bidAtProjectId == null) {
                hashMap[item] = bid
            } else if (bid < bidAtProjectId) {
                hashMap[item] = bid
            }
        }

        hashMap.values.forEach {
            result += it.toLong()
        }

        result
    }
}