day 10b complete

day10/day 10b/sort.go

@@ -0,0 +1,39 @@
+package main
+
+func mergeSort(nums []int, start int, end int) []int {
+	if start == end {
+		return []int{nums[start]}
+	}
+
+	var mid int = ((end - start) / 2) + start
+
+	//Assign values back into Left and right
+	left := mergeSort(nums, start, mid)
+	right := mergeSort(nums, mid+1, end)
+
+	var combined []int
+
+	//Pointers for new array
+	leftPointer, rightPointer := 0, 0
+
+	for leftPointer <= len(left)-1 || rightPointer <= len(right)-1 {
+
+		if leftPointer == len(left) {
+			addValue(&combined, right[rightPointer], &rightPointer)
+		} else if rightPointer == len(right) {
+			addValue(&combined, left[leftPointer], &leftPointer)
+		} else {
+			if left[leftPointer] <= right[rightPointer] {
+				addValue(&combined, left[leftPointer], &leftPointer)
+			} else {
+				addValue(&combined, right[rightPointer], &rightPointer)
+			}
+		}
+	}
+	return combined
+}
+
+func addValue(nums *[]int, value int, pointer *int) {
+	*nums = append(*nums, value)
+	*pointer++
+}