added quick-sort.go

quick-sort/quick-sort.go

@@ -0,0 +1,70 @@
+// ====================================================
+// Data-Structures-with-Go Copyright(C) 2017 Furkan Türkal
+// This program comes with ABSOLUTELY NO WARRANTY; This is free software,
+// and you are welcome to redistribute it under certain conditions; See
+// file LICENSE, which is part of this source code package, for details.
+// ====================================================
+
+package main
+
+import "fmt"
+
+
+func Swap(a *int, b *int){
+	t := *a
+	*a = *b
+	*b = t
+}
+
+func Partition(arr []int, start, end int) int {
+	
+	pivot := arr[end]
+
+	//Index of smaller element
+	var i int = (start - 1)
+
+	for j := start; j <= end - 1; j++ {
+		//If current element is smaller than or equal to pivot
+		if(arr[j] <= pivot){
+			i++
+			Swap(&arr[i], &arr[j])
+		}
+	}
+
+	Swap(&arr[i + 1], &arr[end])
+
+	return (i + 1)
+}
+
+/*The main function that implements QuickSort
+	arr[] -> Array to be sorted
+	start -> Starting index
+	end   -> Ending index
+*/
+func QuickSort(arr []int, start, end int) {
+	if(start < end){
+		//pi is partitioning index, arr[p] is now at right place
+		var pi int = Partition(arr, start, end)
+
+		//Separately sort elements before partition and after partition
+		QuickSort(arr, start, pi - 1)
+		QuickSort(arr, pi + 1, end)
+	}
+}
+
+func PrintArray(arr []int, size int){
+	for i:=0; i < size; i++ {
+		fmt.Printf("%d ", arr[i])
+	}
+	fmt.Printf("\n")
+}
+
+func main() {
+	arr := []int{10, 7, 8, 9, 1, 5}
+	var n int = len(arr)
+
+	QuickSort(arr, 0, n - 1)
+
+	fmt.Println("Sorted array is: ")
+	PrintArray(arr, n)
+}