Create Merge sort

Merge sort

@@ -0,0 +1,78 @@
+//Merge sort
+
+import java.util.*;
+
+class Merge_Sort {
+	static void printArray(int arr[]) {
+        StringBuffer sb=new StringBuffer("");
+        int n = arr.length;
+
+        for(int i = 0; i < n; ++i)
+            sb.append(arr[i] + " ");
+
+        System.out.println(sb.toString());
+    }
+
+	public static void main(String args[]) {
+		Scanner sc = new Scanner(System.in);
+		int T = sc.nextInt();
+
+		while(T > 0) {
+			int n = sc.nextInt();
+			Merge_Sort ms = new Merge_Sort();
+			int arr[] = new int[n];
+
+			for(int i = 0; i < n; i++)
+				arr[i] = sc.nextInt();
+
+			Solution g = new Solution();
+			g.mergeSort(arr, 0, arr.length - 1);
+			ms.printArray(arr);
+		  T--;
+		}
+	}
+}
+
+class Solution {
+    void merge(int arr[], int l, int m, int r) {
+        ArrayList<Integer> temp = new ArrayList<>();
+        int left = l;
+        int right = m + 1;
+
+        while(left <= m && right <= r) {
+            if(arr[left] <= arr[right]) {
+                temp.add(arr[left]);
+                left++;
+            }
+            else {
+                temp.add(arr[right]);
+                right++;
+            }
+        }
+
+        while(left <= m) {
+            temp.add(arr[left]);
+            left++;
+        }
+
+        while(right <= r) {
+            temp.add(arr[right]);
+            right++;
+        }
+
+        for(int i = l; i <= r; i++) {
+            arr[i] = temp.get(i - l);
+        }
+    }
+
+    void mergeSort(int arr[], int l, int r) {
+        if(l >= r) {
+            return;
+        }
+
+        int mid = (l + r) / 2;
+        mergeSort(arr, l, mid);
+        mergeSort(arr, mid + 1, r);
+        merge(arr, l, mid, r);
+    }
+}