type relativeAllocProblem struct {
	items            []relativeAllocItem
	ascendingIndices []int
}

// initIndices fills in ascendingIndices and sorts them
func (rap *relativeAllocProblem) initIndices() *relativeAllocProblem {
	rap.ascendingIndices = make([]int, len(rap.items)*2)
	for idx := 0; idx < len(rap.ascendingIndices); idx++ {
		rap.ascendingIndices[idx] = idx
	}