Merge pull request #62 from arshadpatel/myfeature

Implemented Algorithm of Merge Sort in Java #45

CONTRIBUTING.md

@@ -19,3 +19,9 @@
 
 - GitHub: https://github.com/Mansiprajapatii
 ```
+
+```markdown
+#### Name: Arshad M. Patel
+
+- GitHub: https://github.com/arshadpatel
+```

JAVA/MergeSortAlgo.java

@@ -0,0 +1,58 @@
+public class MergeSortAlgo {
+    public static void main(String[] args) {
+        int[] arr = { 2, 7, 8, 9, 1, 3, 4, 5 };
+        int low = 0;
+
+        int high = arr.length - 1;
+        mergeSort(arr, low, high);
+        for (int i = 0; i < arr.length; i++) {
+            System.out.print(arr[i] + " ");
+        }
+
+    }
+
+    static void mergeSort(int arr[], int low, int high) {
+        if (low < high) {
+            int mid = (low + high) / 2;
+            mergeSort(arr, low, mid);
+            mergeSort(arr, mid + 1, high);
+            mergefunc(arr, low, mid, high);
+        }
+    }
+
+    static void mergefunc(int[] arr, int low, int mid, int high) {
+        int n1 = mid + 1 - low;
+        int n2 = high - mid;
+        int[] left = new int[n1];
+        int[] right = new int[n2];
+        for (int i = 0; i < n1; i++) {
+            left[i] = arr[low + i];
+        }
+        for (int i = 0; i < n2; i++) {
+            right[i] = arr[mid + 1 + i];
+        }
+        int i = 0, j = 0, k = low;
+        while (i < n1 && j < n2) {
+            if (left[i] <= right[j]) {
+                arr[k] = left[i];
+                i++;
+                k++;
+            } else {
+                arr[k] = right[j];
+                j++;
+                k++;
+            }
+        }
+
+        while (i < n1) {
+            arr[k] = left[i];
+            i++;
+            k++;
+        }
+        while (j < n2) {
+            arr[k] = right[j];
+            j++;
+            k++;
+        }
+    }
+}