diff --git a/lists/mergeWithoutExtraSpace.java b/lists/mergeWithoutExtraSpace.java
new file mode 100644
index 0000000..f07602a
--- /dev/null
+++ b/lists/mergeWithoutExtraSpace.java
@@ -0,0 +1,72 @@
+package lists;
+import java.io.*;
+import java.util.*;
+
+class GFG {
+    // Driver code
+    public static void main(String[] args) throws Exception {
+        BufferedReader br =
+            new BufferedReader(new InputStreamReader(System.in));
+        int t = Integer.parseInt(br.readLine().trim());
+        while (t-- > 0) {
+            String inputLine[] = br.readLine().trim().split(" ");
+            int n = Integer.parseInt(inputLine[0]);
+            int m = Integer.parseInt(inputLine[1]);
+            int arr1[] = new int[n];
+            int arr2[] = new int[m];
+            inputLine = br.readLine().trim().split(" ");
+            for (int i = 0; i < n; i++) {
+                arr1[i] = Integer.parseInt(inputLine[i]);
+            }
+            inputLine = br.readLine().trim().split(" ");
+            for (int i = 0; i < m; i++) {
+                arr2[i] = Integer.parseInt(inputLine[i]);
+            }
+
+            new Solution().merge(arr1, arr2, n, m);
+
+            StringBuffer str = new StringBuffer();
+            for (int i = 0; i < n; i++) {
+                str.append(arr1[i] + " ");
+            }
+            for (int i = 0; i < m; i++) {
+                str.append(arr2[i] + " ");
+            }
+            System.out.println(str);
+        }
+    }
+}// } Driver Code Ends
+
+
+class Solution {
+
+    public void merge(int arr1[], int arr2[], int n, int m) {
+       
+       int p1=0;
+       int p2=0;
+       int p3=n-1;
+       
+     
+           while(p1<=p3 && p2<m)
+           {
+                   if(arr1[p1]<arr2[p2])
+                        p1++;
+                    else
+                    {
+                        int temp=arr1[p3];
+                        arr1[p3]=arr2[p2];
+                        arr2[p2]=temp;
+                        
+                        p2++;
+                        p3--;
+                    }
+                    
+           }
+           
+           Arrays.sort(arr1);
+           Arrays.sort(arr2);
+           
+            
+       
+    }
+}
\ No newline at end of file