Solution to Codility Chapter 10: Peaks

	val input = Array(1,2,3,4,3,4,1,2,3,4,6,2)
	println(evaluate(input))
	def evaluate(arr: Array[Int]): Int = {
	val p = peaks(arr)
	var i = arr.length
	while (i > 0) {
	if (arr.length % i == 0
	&& canSplit(arr.length, p , arr.length/i)) {
	return i
	}
	i -= 1
	}
	0
	}
	def canSplit(arrLength: Int,
	peaks: IndexedSeq[Int],
	numberOfChunks: Int): Boolean = {
	// checks if we can split into numberOfChunks chunks
	def aux(currentChunkIndex: Int, peakIndex: Int): Boolean = {
	val endOfChunk = currentChunkIndex + numberOfChunks
	if (currentChunkIndex == arrLength) true
	else if (peakIndex == peaks.length) false
	else {
	if (peaks(peakIndex) >= currentChunkIndex
	&& peaks(peakIndex) < endOfChunk) {
	aux(endOfChunk, peakIndex + 1)
	}
	else {
	aux(currentChunkIndex, peakIndex + 1)
	}
	}
	}
	aux(0, 0)
	}
	def peaks(arr: Array[Int]): IndexedSeq[Int] = {
	(1 until arr.length - 1).filter ( i =>
	arr(i) > arr(i+1) && arr(i) > arr(i-1)
	)
	}

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