diff --git a/BubbleSort.java b/BubbleSort.java
new file mode 100644
index 0000000..0125934
--- /dev/null
+++ b/BubbleSort.java
@@ -0,0 +1,33 @@
+
+public class BubbleSort {
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+		
+		if(args.length == 0) {
+			System.out.println("Usage: LetterGrade <numeric-score>");
+			return;
+		}
+		int data[] = new int[args.length];
+		int tamp = 0;
+
+		for(int i=0;i<data.length;i++){
+			data[i] = Integer.parseInt(args[i]);
+		}
+
+		for(int i=0;i<data.length;i++){
+			for(int j=0;j<data.length;j++){
+				if(data[i] < data[j]){
+					tamp = data[i];
+					data[i] = data[j];
+					data [j] = tamp;	
+				}
+			}
+		}
+
+		for(int i=0;i<data.length;i++){
+			System.out.println(data[i]);
+		}
+        
+	}
+}
diff --git a/Calendar.java b/Calendar.java
new file mode 100644
index 0000000..96e2c51
--- /dev/null
+++ b/Calendar.java
@@ -0,0 +1,29 @@
+
+public class Calendar {
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+		
+		if(args.length != 1) {
+			System.out.println("Usage: LetterGrade <numeric-score>");
+			return;
+		}
+		
+        int month = Integer.parseInt(args[0]);
+        switch(month){
+        	case 1 : System.out.println("January");break;
+        	case 2 : System.out.println("February");break;
+        	case 3 : System.out.println("March");break;
+        	case 4 : System.out.println("April");break;
+        	case 5 : System.out.println("May");break;
+        	case 6 : System.out.println("June");break;
+        	case 7 : System.out.println("July");break;
+        	case 8 : System.out.println("August");break;
+        	case 9 : System.out.println("September");break;
+        	case 10 : System.out.println("October");break;
+        	case 11 : System.out.println("November");break;
+        	case 12 : System.out.println("December");break;
+        	default : System.out.println("Invalid input");break;
+                }
+	}
+}
diff --git a/Day.java b/Day.java
new file mode 100644
index 0000000..a1e54a8
--- /dev/null
+++ b/Day.java
@@ -0,0 +1,32 @@
+
+public class Day {
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+		
+		if(args.length != 2) {
+			System.out.println("Usage: LetterGrade <numeric-score>");
+			return;
+		}
+		
+        int month = Integer.parseInt(args[0]);
+        int year = Integer.parseInt(args[1]);
+        switch(month){
+                case 1 :
+                case 3 :
+                case 5 :
+                case 7 :
+                case 8 :
+                case 10:
+                case 12: System.out.println("31 Days");break;
+                case 4 :
+                case 6 :
+                case 9 : 
+                case 11 : System.out.println("30 Days");break;
+                case 2 : if(year % 4 == 0 && year % 100 != 0 || year % 400 == 0)
+                                System.out.println("29 Days");
+                        else System.out.println("28 Days");break;
+        	default : System.out.println("Invalid input");break;
+                }
+        }
+}
diff --git a/Factorial.java b/Factorial.java
new file mode 100644
index 0000000..8cbb1f9
--- /dev/null
+++ b/Factorial.java
@@ -0,0 +1,20 @@
+
+public class Factorial {
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+		
+		if(args.length != 1) {
+			System.out.println("Usage: LetterGrade <numeric-score>");
+			return;
+		}
+		
+        int n = Integer.parseInt(args[0]);
+        int result = 1;
+        for(int i=n;i>0;i--){
+                result *= i;
+        }
+        
+        System.out.println(result);
+        }
+}
diff --git a/FactorialRecursive.java b/FactorialRecursive.java
new file mode 100644
index 0000000..0d31d30
--- /dev/null
+++ b/FactorialRecursive.java
@@ -0,0 +1,22 @@
+
+public class FactorialRecursive {
+
+	public static  int factorial(int n){
+		if(n==1){
+			return n;
+		}
+		else return n * factorial(n-1);
+	}
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+		
+		if(args.length != 1) {
+			System.out.println("Usage: LetterGrade <numeric-score>");
+			return;
+		}
+		
+        int n = Integer.parseInt(args[0]);
+        int result = factorial(n);
+        System.out.println(result);
+        }
+}
diff --git a/HelloWorld.java b/HelloWorld.java
new file mode 100644
index 0000000..ad4bbcf
--- /dev/null
+++ b/HelloWorld.java
@@ -0,0 +1,24 @@
+
+public class HelloWorld {
+
+	public static void main(String[] args) {
+		// TODO Auto-generated method stub
+		
+		if(args.length != 1) {
+			System.out.println("Usage: LetterGrade <numeric-score>");
+			return;
+		}
+		
+        int score = Integer.parseInt(args[0]);
+        if(score > 80){
+        	System.out.println("A");
+        }
+        else if(score > 60){
+        	System.out.println("B");
+        }
+        else System.out.println("C");
+
+        
+	}
+
+}