From 39abfd068b31301f43436bd5baad7dbaf68edc8d Mon Sep 17 00:00:00 2001
From: Zykiel <48471587+ZykielErx@users.noreply.github.com>
Date: Wed, 30 Oct 2019 18:20:50 +0800
Subject: [PATCH] Added Cycle Sort (#340)

Added Cycle Sort
---
 README.md           |   1 +
 sorting/CycleSort.c | 106 ++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 107 insertions(+)
 create mode 100644 sorting/CycleSort.c

diff --git a/README.md b/README.md
index 28f09971d..aff09d8ce 100644
--- a/README.md
+++ b/README.md
@@ -55,6 +55,7 @@ C
 	- BogoSort
 	- comb_sort
 	- CountingSort
+	- Cycle Sort
 	- gnome_sort
 	- PartitionSort
 	- ShellSort
diff --git a/sorting/CycleSort.c b/sorting/CycleSort.c
new file mode 100644
index 000000000..204647006
--- /dev/null
+++ b/sorting/CycleSort.c
@@ -0,0 +1,106 @@
+// Sorting of array list using cycle sort
+#include <stdio.h>
+#include <stdlib.h>
+
+// Displays the array, passed to this method
+void display(int arr[], int n){
+    
+    int i;
+    for(i = 0; i < n; i++){
+        printf("%d ", arr[i]);
+    }
+    
+    printf("\n");
+    
+}
+
+// Swap function to swap two values
+void swap(int *first, int *second){
+    
+    int temp = *first;
+    *first = *second;
+    *second = temp;
+    
+}
+
+// Function sort the array using Cycle sort
+void cycleSort(int arr[], int n)
+{
+    // count number of memory writes
+    int writes = 0;
+
+    // traverse array elements and put it to on
+    // the right place
+    for (int cycle_start = 0; cycle_start <= n - 2; cycle_start++) {
+        // initialize item as starting point
+        int item = arr[cycle_start];
+
+        // Find position where we put the item. We basically
+        // count all smaller elements on right side of item.
+        int pos = cycle_start;
+        for (int i = cycle_start + 1; i < n; i++)
+            if (arr[i] < item)
+                pos++;
+
+        // If item is already in correct position
+        if (pos == cycle_start)
+            continue;
+
+        // ignore all duplicate elements
+        while (item == arr[pos])
+            pos += 1;
+
+        // put the item to it's right position
+        if (pos != cycle_start) {
+            swap(&item, &arr[pos]);
+            writes++;
+        }
+
+        // Rotate rest of the cycle
+        while (pos != cycle_start) {
+            pos = cycle_start;
+
+            // Find position where we put the element
+            for (int i = cycle_start + 1; i < n; i++)
+                if (arr[i] < item)
+                    pos += 1;
+
+            // ignore all duplicate elements
+            while (item == arr[pos])
+                pos += 1;
+
+            // put the item to it's right position
+            if (item != arr[pos]) {
+                swap(&item, &arr[pos]);
+                writes++;
+            }
+        }
+    }
+
+}
+
+
+// Driver program to test above function
+int main()
+{
+    int n;  // Size of array elements
+
+    printf("Enter size of array:\n");
+    scanf("%d", &n); // E.g. 8
+    
+    printf("Enter the elements of the array\n");
+    int i;
+    int arr[n];
+    for(i = 0; i < n; i++){
+        scanf("%d", &arr[i] );
+    }
+
+    printf("Original array: ");
+    display(arr, n);
+
+    cycleSort(arr, n);
+    printf("Sorted array: ");
+    display(arr, n);
+
+    return 0;
+}