Given an array of n integers and size k, where k < n, find the maximum sum of k consecutive elements in the array.

maximumSumOfKConsecutiveElements.kt

fun findMaximumSum(a: IntArray, k: Int): Int {
    var currentSum: Int = 0
    var maximumSum: Int
    
    for (i in 0 until k) {
        currentSum += a[i]
    }

    maximumSum = currentSum

    for (i in k until a.size) {
        // Discard the left most element
        currentSum -= a[i - k]
        // Included the current element
        currentSum += a[i]
        if (maximumSum < currentSum) {
            maximumSum = currentSum
        }
    }
    return maximumSum
}

fun main() {
    val a = intArrayOf(1, 4, 2, 10, 2, 3, 1, 0, 20)
    val k = 4
    println("Maximum sum: " + findMaximumSum(a, k))
}