diff --git a/OOP/Java/Lab/Week9/arrange_array.java b/OOP/Java/Lab/Week9/arrange_array.java
new file mode 100644
index 0000000..28c5df8
--- /dev/null
+++ b/OOP/Java/Lab/Week9/arrange_array.java
@@ -0,0 +1,20 @@
+
+import java.util.*;
+
+public class arrange_array {
+    public static void main(String[] args) {
+        int n;
+        Scanner sc = new Scanner(System.in);
+        System.out.println("Enter number of strings you would like");
+        n = Integer.parseInt(sc.nextLine());
+        System.out.println("Enter your strings");
+        String[] arr = new String[n];
+        for(int i = 0;i<n;i++){
+            arr[i] = sc.nextLine();
+        }
+        Collections.sort(arr);// or use some sorting technique with arr[i].compareTo(arr[i+1])
+        for(int i = 0;i<n;i++){
+            System.out.print(arr[i]+" ");
+        }
+    }
+}
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diff --git a/OOP/Java/Lab/Week9/concat_5.java b/OOP/Java/Lab/Week9/concat_5.java
new file mode 100644
index 0000000..39e9100
--- /dev/null
+++ b/OOP/Java/Lab/Week9/concat_5.java
@@ -0,0 +1,15 @@
+import java.util.Scanner;
+public class concat_5 {
+    public static void main(String[] args) {
+        Scanner sc = new Scanner(System.in);
+        String concatString = "";
+        System.out.println("Enter five strings separately:");
+        for (int i = 1;  i<= 5; i++) {
+            System.out.print("Enter string " + i + ": ");
+            String inputString = sc.nextLine();
+            concatString.concat(inputString);
+
+        }
+        System.out.println("Concatenated String: " + concatString);   
+    }
+}
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diff --git a/OOP/Java/Lab/Week9/replacing.java b/OOP/Java/Lab/Week9/replacing.java
new file mode 100644
index 0000000..405fd5a
--- /dev/null
+++ b/OOP/Java/Lab/Week9/replacing.java
@@ -0,0 +1,27 @@
+import java.util.Scanner;
+class replacing{
+    public static void main(String[] args) {
+        Scanner in=new Scanner(System.in);
+        System.out.println("Enter the Lines...");
+        String str=in.nextLine();
+        str.trim();
+        System.out.println("Enter the word to be removed");
+        String word=in.nextLine();
+        StringBuffer strbuf= new StringBuffer(str);
+        if(str.contains(word))
+        {
+           
+            int index=str.indexOf(word);
+            int wlen=word.length();
+            String
+            String rep="";
+            for(int i=0;i<wlen;i++)
+            {
+                rep+="*";
+            }
+            strbuf.replace(index,index+wlen,rep);
+        }
+        System.out.println("Replaced String=\n"+strbuf);
+        
+    }
+}
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diff --git a/OOP/Java/Lab/Week9/telephone.java b/OOP/Java/Lab/Week9/telephone.java
new file mode 100644
index 0000000..5c6066d
--- /dev/null
+++ b/OOP/Java/Lab/Week9/telephone.java
@@ -0,0 +1,13 @@
+import java.util.Scanner;
+public class telephone{
+    public static void main(String[] args) {
+        Scanner sc = new Scanner(System.in);
+        System.out.println("Enter the phone number as (555) 555-5555");
+        String phoneNumber = sc.nextLine();
+        phoneNumber = phoneNumber.replaceAll("[^0-9]", "");
+        String areaCode = phoneNumber.substring(0, 3);
+        String sevenDigit = phoneNumber.substring(3);
+        System.out.println("Area Code:"+areaCode);
+        System.out.println("Seven digit phone number:"+sevenDigit);
+    }
+}
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diff --git a/OOP/Java/Lab/Week9/three_letter.java b/OOP/Java/Lab/Week9/three_letter.java
new file mode 100644
index 0000000..a1a8369
--- /dev/null
+++ b/OOP/Java/Lab/Week9/three_letter.java
@@ -0,0 +1,24 @@
+import java.util.Scanner;
+
+public class three_letter {
+    public static void main(String[] args) {
+        Scanner sc = new Scanner(System.in);
+        System.out.print("Enter a five-letter word: ");
+        String word = sc.nextLine();
+        
+        if (word.length() != 5) {
+            System.out.println("Please enter a valid five-letter word.");
+        } else {
+            for (int i = 0; i < 5; i++) {
+                for (int j = 0; j < 5; j++) {
+                    for (int k = 0; k < 5;s k++) {
+                        if (i != j && j != k && i != k) {
+                            String threeLetterWord = "" + word.charAt(i) + word.charAt(j) + word.charAt(k);
+                            System.out.println(threeLetterWord);
+                        }
+                    }
+                }
+            }
+        }
+    }
+}
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