diff --git a/December 01/dec1.java b/December 01/dec1.java
new file mode 100644
index 0000000..4294d35
--- /dev/null
+++ b/December 01/dec1.java	
@@ -0,0 +1,27 @@
+import java.util.Scanner;
+public class dec1 {
+        public static void main(String[] args) {
+            int[] cricket = new int[11];
+            int score = 0;
+            int best_batsmen = 0;
+            Scanner scanner = new Scanner(System.in);
+            System.out.print("Enter number of batsmen:");
+            int n = scanner.nextInt();
+    
+            for (int i = 0; i < n; i++) {
+                System.out.print("Enter runs scored by batsmen " + (i + 1) + ":");
+                cricket[i] = scanner.nextInt();
+                score = score + cricket[i];
+            }
+            int largest = cricket[0];
+            for (int i = 1; i < n; i++) {
+                if (cricket[i] > largest) {
+                    largest = cricket[i];
+                    best_batsmen = i;
+                }
+            }
+            System.out.println("Total runs scores by the team is " + score + " and the best batsmen is "
+                    + (best_batsmen + 1) + " .He scored " + largest + " Runs!!");
+            scanner.close();
+        }   
+}
diff --git a/December 02/dec2.java b/December 02/dec2.java
new file mode 100644
index 0000000..4a15fd0
--- /dev/null
+++ b/December 02/dec2.java	
@@ -0,0 +1,38 @@
+import java.util.Scanner;
+public class dec2 {
+    public class december2 {
+            public static void main(String[] args) {
+             System.out.println("Enter number of Purchase to analyse : ");
+             Scanner scanner = new Scanner(System.in);
+             int size = scanner.nextInt();
+             int[] productId = new int[size];
+             System.out.println("Enter product ID ");
+             for(int i=0;i<size;i++){
+                System.out.println("No " + (i+1) + ":");
+                productId[i] = scanner.nextInt();
+             }
+             int[] frequencyArray = new int[size];
+                boolean[] visited = new boolean[size];
+                for (int i = 0; i < size; i++) {
+                    if (!visited[i]) {
+                        int count = 1;
+                        for (int j = i + 1; j < size; j++) {
+                            if (productId[i] == productId[j]) {
+                                visited[j] = true;
+                                count++;
+                            }
+                        }
+                        frequencyArray[i] = count;
+                    }
+                }
+                System.out.println("Frequency of each element:");
+                for (int i = 0; i < size; i++) {
+                    if (!visited[i]) {
+                        System.out.println(productId[i] + ": " + frequencyArray[i] + " times");
+                    }
+                }
+                scanner.close();
+            } 
+    }
+}    
+
diff --git a/December 03/dec3.java b/December 03/dec3.java
new file mode 100644
index 0000000..a333819
--- /dev/null
+++ b/December 03/dec3.java	
@@ -0,0 +1,26 @@
+import java.util.Scanner;
+public class dec3 {
+    public class december3 {
+        public static void main(String[] args) {
+            Scanner scanner = new Scanner(System.in);
+            System.out.print("Enter Number of buildings : ");
+            int size = scanner.nextInt();
+            int[] array = new int[size];
+            System.out.println("Enter hight of the building:");
+    
+            for (int i = 0; i < size; i++) {
+                System.out.print("Building " + (i + 1) + ": ");
+                array[i] = scanner.nextInt();
+            }
+            int count = 0;
+            for (int i = 1; i < size; i++) {
+                if (array[i] > array[i - 1]) {
+                    count++;
+                }
+            }
+            System.out.println("No of building that can see the Sun rise ! : " + (count + 1));
+            scanner.close();
+        }
+    }
+    
+}
diff --git a/December 04/dec4.java b/December 04/dec4.java
new file mode 100644
index 0000000..90a7257
--- /dev/null
+++ b/December 04/dec4.java	
@@ -0,0 +1,32 @@
+import java.util.Scanner;
+public class dec4 {
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        System.out.print("Enter a word: ");
+        String word = scanner.nextLine();
+        String smallestPalindrome = findSmallestPalindrome(word);
+        System.out.println("Smallest palindrome: " + smallestPalindrome);
+        scanner.close();
+    }
+    private static String findSmallestPalindrome(String word) {
+        int length = word.length();
+
+        for (int i = 0; i < length; i++) {
+            for (int j = i + 1; j <= length; j++) {
+                String substring = word.substring(i, j);
+                if (isPalindrome(substring)) {
+                    return substring;
+                }
+            }
+        }
+
+        return "No palindrome found";
+    }
+
+    private static boolean isPalindrome(String str) {
+        str = str.replaceAll("\\s", "").toLowerCase();
+        return str.equals(new StringBuilder(str).reverse().toString());
+    }
+}
+
+    
diff --git a/December 05/dec5.java b/December 05/dec5.java
new file mode 100644
index 0000000..f4f2a69
--- /dev/null
+++ b/December 05/dec5.java	
@@ -0,0 +1,26 @@
+import java.util.Scanner;
+public class dec5 {
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        System.out.println("Enter the number of stealing attempts :");  
+        int n = scanner.nextInt();
+        int tot=0,money=0;
+        int[] array = new int[n];
+        for(int i=0;i<n;i++){
+            System.out.println("enter amount stolen in" + (i+1) + "th attempt");
+            int v =scanner.nextInt();
+            array[i]= v;
+            tot = tot+v;
+        
+        }
+        int avg =tot/n;
+        for(int i=0;i<n;i++){
+            if(array[i]>=avg){
+                money= money + array[i];
+            }
+        }
+        System.out.println("the total amount of money stolen by the thieves who stole more than or equal to the average amount stolen by the group="+money);
+        scanner.close();
+    }  
+}
+//retry
\ No newline at end of file
diff --git a/December 06/dec6.java b/December 06/dec6.java
new file mode 100644
index 0000000..ac3eb13
--- /dev/null
+++ b/December 06/dec6.java	
@@ -0,0 +1,37 @@
+import java.util.ArrayList;
+import java.util.Scanner;
+
+public class dec6 {
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        System.out.print("Enter number of words in the secret msg:");
+        int n = scanner.nextInt();
+        String[] array = new String[n];
+        for (int i = 0; i < n; i++) {
+            System.out.println("Enter word no " + (i + 1));
+            String v = scanner.next();
+            array[i] = v;
+        }
+        ArrayList<String> finalList = new ArrayList<>();
+        finalList.add(array[0]);
+
+        for (int i = 1; i < n; i++) {
+            String a = finalList.get(finalList.size() - 1);
+            String b = array[i];
+            int m = 0;
+
+            for (int x = 0; x < a.length(); x++) {
+                if (a.charAt(x) != b.charAt(x)) {
+                    m++;
+                }
+            }
+
+            if (m <= 1) {
+                finalList.add(b);
+            }
+        }
+
+        System.out.println(finalList);
+        scanner.close();
+    }
+}
diff --git a/December 07/dec7.java b/December 07/dec7.java
new file mode 100644
index 0000000..5a6f3aa
--- /dev/null
+++ b/December 07/dec7.java	
@@ -0,0 +1,28 @@
+import java.util.Scanner;
+public class dec7 {
+    public static void main(String[] args) {
+        Scanner scanner=new Scanner (System.in);
+        System.out.print("Enter the width of the rectangle: ");
+        double width = scanner.nextDouble();
+        System.out.print("Enter the height of the rectangle: ");
+        double height = scanner.nextDouble(); 
+        System.out.print("Enter the radius of the circle: ");
+        double radius = scanner.nextDouble();
+ 
+        boolean canFit = isRectangleInCircle(width, height, radius);
+        if (canFit) {
+            System.out.println("The rectangle can fit inside the circle.");
+        } else {
+            System.out.println("The rectangle cannot fit inside the circle.");
+        }
+
+        scanner.close();
+    }
+
+    private static boolean isRectangleInCircle(double width, double height, double radius) {
+       double diagonal = Math.sqrt(width * width + height * height);
+        return diagonal <= (2 * radius);
+    }
+}
+
+    
\ No newline at end of file
diff --git a/December 08/dec8.java b/December 08/dec8.java
new file mode 100644
index 0000000..47cb65a
--- /dev/null
+++ b/December 08/dec8.java	
@@ -0,0 +1,64 @@
+import java.util.Scanner;
+public class dec8 {
+        public static void main(String[] args) {
+            
+            System.out.print("Enter number of Rows/column for the square matrix:");
+            Scanner scanner= new Scanner(System.in);
+            int n= scanner.nextInt();
+            int[][] magicSquare = findPath(n);
+
+            displayMagicSquare(magicSquare);
+            scanner.close();
+        }
+        
+
+        
+        private static int[][] findPath(int n) {
+            int[][] magicSquare = new int[n][n];
+            int i = n / 2;
+            int j = n - 1;
+    
+            for (int num = 1; num <= n * n;) {
+                if (i == -1 && j == n) {
+                    j = n - 2;
+                    i = 0;
+                } else {
+                    if (j == n) {
+                        j = 0;
+                    }
+                    if (i < 0) {
+                        i = n - 1;
+                    }
+                }
+                if (magicSquare[i][j] != 0) {
+                    j -= 2;
+                    i++;
+                    continue;
+                } else {
+
+                    magicSquare[i][j] = num++;
+                }
+    
+                j++;
+                i--;
+            }
+            return magicSquare;
+        }
+
+
+
+        private static void displayMagicSquare(int[][] magicSquare) {
+            System.out.println("Magic Square:");
+    
+            for (int i = 0; i < magicSquare.length; i++) {
+                for (int j = 0; j < magicSquare[i].length; j++) {
+                    System.out.print(magicSquare[i][j] + "\t");
+                }
+                System.out.println();
+            }
+            
+        }
+    
+      
+    
+}
diff --git a/December 09/dec9.java b/December 09/dec9.java
new file mode 100644
index 0000000..2fc0711
--- /dev/null
+++ b/December 09/dec9.java	
@@ -0,0 +1,23 @@
+import java.util.Scanner;
+
+public class dec9 {
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+
+        System.out.print("Enter the camel case string: ");
+        String camelCaseString = scanner.next();
+
+        int wordCount = 1; 
+        for (int i = 0; i < camelCaseString.length(); i++) {
+            char currentChar = camelCaseString.charAt(i);
+
+          
+            if (Character.isUpperCase(currentChar)) {
+                wordCount++;
+            }
+        }
+        System.out.println("Number of words: " + wordCount);
+
+        scanner.close();
+    }
+}
\ No newline at end of file
diff --git a/December 10/dec10.java b/December 10/dec10.java
new file mode 100644
index 0000000..b10eee6
--- /dev/null
+++ b/December 10/dec10.java	
@@ -0,0 +1,16 @@
+public class dec10 {
+    public static void main(String[] args) {
+  
+        String[] empData = {"100 Shivnash Kumar", "110 Ragul Gupta"};
+
+        for (String empRecord : empData) {
+            String empnameSubstring = getEmpnameSubstring(empRecord);
+            System.out.println(empnameSubstring);
+        }
+    }
+    private static String getEmpnameSubstring(String empRecord) {
+
+        int empnameStartIndex = empRecord.indexOf(" ") + 1;
+        return empRecord.substring(empnameStartIndex);
+    }
+}
diff --git a/December 11/dec11.java b/December 11/dec11.java
new file mode 100644
index 0000000..f900adb
--- /dev/null
+++ b/December 11/dec11.java	
@@ -0,0 +1,13 @@
+import java.util.Scanner;
+public class dec11 {
+        public static void main(String[] args) {
+            Scanner scanner = new Scanner(System.in);
+            System.out.print("Enter 2 Numbers : ");
+            int num1 = scanner.nextInt();
+            int num2 = scanner.nextInt();
+            int sum = num1+num2;
+            System.out.println("Sum in binary: " + Integer.toBinaryString(sum));
+            scanner.close();
+        }
+    }
+
diff --git a/December 12/dec12.java b/December 12/dec12.java
new file mode 100644
index 0000000..93a13cc
--- /dev/null
+++ b/December 12/dec12.java	
@@ -0,0 +1,33 @@
+import java.util.Arrays;
+import java.util.Scanner;  
+public class dec12 {
+        public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        System.out.print("Enter the content of Box1 seperated by coma: ");
+        String[] box1 = scanner.nextLine().split(", ");
+        System.out.print("Enter the content of Box2 : ");
+        String[] box2 = scanner.nextLine().split(", ");
+        System.out.print("Enter the content of Box3 : ");
+        String[] box3 = scanner.nextLine().split(", ");
+        String result = findGoldBox(box1, box2, box3);
+
+        System.out.println(result);
+
+        scanner.close();
+    }
+    private static String findGoldBox(String[] box1, String[] box2, String[] box3) {
+        String[] sortedBoxes = {box1[2], box2[2], box3[2]}; 
+
+        Arrays.sort(sortedBoxes);
+
+        if (sortedBoxes[1].equals("Gold")) {
+            return "The box containing the Gold is Box2";
+        } else if (sortedBoxes[0].equals("Gold")) {
+            return "The box containing the Gold is Box1";
+        } else {
+            return "The box containing the Gold is Box3";
+        }
+    }
+}
+
+    
diff --git a/December 13/dec13.java b/December 13/dec13.java
new file mode 100644
index 0000000..602ec3d
--- /dev/null
+++ b/December 13/dec13.java	
@@ -0,0 +1,64 @@
+ import java.util.Scanner;
+public class dec13 {
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        System.out.print("Enter the letter-encoded phone number: ");
+        String encodedPhoneNumber = scanner.nextLine().toUpperCase();
+        String numericalForm = decodePhoneNumber(encodedPhoneNumber);
+        System.out.println("Numerical form: " + numericalForm);
+        scanner.close();
+    }
+    private static String decodePhoneNumber(String encodedPhoneNumber) {
+        StringBuilder numericalForm = new StringBuilder();
+
+        for (char letter : encodedPhoneNumber.toCharArray()) {
+            int number = getNumberForLetter(letter);
+            if (number != -1) {
+                numericalForm.append(number);
+            }
+        }
+        return numericalForm.toString();
+    }
+    private static int getNumberForLetter(char letter) {
+        switch (letter) {
+            case 'A':
+            case 'B':
+            case 'C':
+                return 2;
+            case 'D':
+            case 'E':
+            case 'F':
+                return 3;
+            case 'G':
+            case 'H':
+            case 'I':
+                return 4;
+            case 'J':
+            case 'K':
+            case 'L':
+                return 5;
+            case 'M':
+            case 'N':
+            case 'O':
+                return 6;
+            case 'P':
+            case 'Q':
+            case 'R':
+            case 'S':
+                return 7;
+            case 'T':
+            case 'U':
+            case 'V':
+                return 8;
+            case 'W':
+            case 'X':
+            case 'Y':
+            case 'Z':
+                return 9;
+            default:
+                return -1;
+        }
+    }
+}
+
+
diff --git a/December 15/dec15.java b/December 15/dec15.java
new file mode 100644
index 0000000..7cb0fef
--- /dev/null
+++ b/December 15/dec15.java	
@@ -0,0 +1,28 @@
+import java.util.Arrays;
+import java.util.Scanner;
+public class dec15 { 
+        public static void main(String[] args) {
+            Scanner scanner= new Scanner(System.in);
+            System.out.println("Enter Input string");
+            String input = scanner.nextLine();
+            int n = input.length();
+            int[] dp = new int[n + 1];
+            dp[0] = 1;
+            int[] lastOccurrence = new int[256];
+            Arrays.fill(lastOccurrence, -1);
+    
+            for (int i = 1; i <= n; i++) {
+                dp[i] = 2 * dp[i - 1];
+    
+                char currentChar = input.charAt(i - 1);
+    
+                if (lastOccurrence[currentChar] != -1) {
+                    dp[i] -= dp[lastOccurrence[currentChar] - 1];
+                }
+    
+                lastOccurrence[currentChar] = i;
+                scanner.close();
+            }
+            System.out.println("Number of distinct subsequences: " + dp[n]);
+        }
+    }
diff --git a/December 19/dec19.java b/December 19/dec19.java
new file mode 100644
index 0000000..de801dd
--- /dev/null
+++ b/December 19/dec19.java	
@@ -0,0 +1,24 @@
+import java.util.Scanner;
+public class dec19 {
+    public static void main(String[] args) {
+        Scanner scanner = new Scanner(System.in);
+        System.out.print("Enter code: ");
+        String ciphertext = scanner.nextLine().toUpperCase();
+        System.out.print("Enter shift number (0 to 25): ");
+        int shift = scanner.nextInt();
+        StringBuilder decryptedMessage = new StringBuilder();
+        for (char ch : ciphertext.toCharArray()) {
+            if (Character.isLetter(ch)) {
+                char base = Character.isUpperCase(ch) ? 'A' : 'a';
+                decryptedMessage.append((char) ((ch - shift - base + 26) % 26 + base));
+            } else {
+                decryptedMessage.append(ch);
+            }
+        }
+        System.out.println("Decrypted Message: " + decryptedMessage);
+        scanner.close();
+    }
+}
+
+    
+
diff --git a/December 29/dec29.java b/December 29/dec29.java
new file mode 100644
index 0000000..ad33dec
--- /dev/null
+++ b/December 29/dec29.java	
@@ -0,0 +1,33 @@
+public class dec29 {
+        public static void main(String[] args) {
+            char[] walk = {'n', 's', 'n', 's', 'n', 's', 'n', 's', 'n', 's'};
+            boolean result = isValidWalk(walk);
+            System.out.println(result ? "TRUE" : "FALSE");
+        }
+        public static boolean isValidWalk(char[] walk) {
+            if (walk.length != 10) {
+                return false; 
+            }
+            int northSouthSteps = 0;
+            int eastWestSteps = 0;
+            for (char direction : walk) {
+                switch (direction) {
+                    case 'n':
+                        northSouthSteps++;
+                        break;
+                    case 's':
+                        northSouthSteps--;
+                        break;
+                    case 'e':
+                        eastWestSteps++;
+                        break;
+                    case 'w':
+                        eastWestSteps--;
+                        break;
+                    default:
+                        return false;
+                }
+            }
+            return northSouthSteps == 0 && eastWestSteps == 0;
+        }
+    }