Create merge sort

merge sort

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+import java.util.Arrays;
+
+class Main
+{
+    // merge arrays : intArray[start...mid] and intArray[mid+1...end]
+    public static void merge(int[] intArray, int[] temp, int start, int mid, int end)
+    {
+        int k = start, i = start, j = mid + 1;
+
+        // traverse through elements of left and right arrays
+        while (i <= mid && j <= end) {
+            if (intArray[i] < intArray[j]) {
+                temp[k++] = intArray[i++];
+            } else {
+                temp[k++] = intArray[j++];
+            }
+        }
+
+        // Copy remaining elements
+        while (i <= mid) {
+            temp[k++] = intArray[i++];
+        }
+
+        // copy temp array back to the original array to reflect sorted order
+        for (i = start; i <= end; i++) {
+            intArray[i] = temp[i];
+        }
+    }
+// sorting intArray[low...high] using iterative approach
+    public static void mergeSort(int[] intArray)
+    {
+        int low = 0;
+        int high = intArray.length - 1;
+
+        // sort array intArray[] using temporary array temp
+        int[] temp = Arrays.copyOf(intArray, intArray.length);
+
+        // divide the array into blocks of size m
+        // m = [1, 2, 4, 8, 16...]
+        for (int m = 1; m <= high - low; m = 2*m)
+        {
+            for (int i = low; i < high; i += 2*m)
+            {
+                int start = i;
+                int mid = i + m - 1;
+                int end = Integer.min(i + 2 * m - 1, high);
+                //call merge routine to merge the arrays
+                merge(intArray, temp, start, mid, end);
+            }
+        }
+    }
+
+    public static void main(String[] args)
+    {
+        //define array to be sorted
+        int[] intArray = { 10,23,-11,54,2,9,-10,45 };
+        //print the original array
+        System.out.println("Original Array : " + Arrays.toString(intArray));
+        //call mergeSort routine
+        mergeSort(intArray);
+        //print the sorted array
+        System.out.println("Sorted Array : " + Arrays.toString(intArray));
+    }
+}