diff --git a/FIRST-java-Q1.java b/FIRST-java-Q1.java
new file mode 100644
index 000000000..c2c484aa0
--- /dev/null
+++ b/FIRST-java-Q1.java
@@ -0,0 +1,21 @@
+//Write a program to print whether a number is even or odd, also take
+//input from the user.
+import java.util.Scanner;
+public class FIRST-java-Q1
+{
+ public static void main(String[] args)
+ {
+ Scanner sc = new Scanner(System.in);
+ System.out.print("Enter a number: ");
+ int num = sc.nextInt();
+
+ if (num % 2 == 0) {
+ System.out.println(num + " is an even number.");
+ }
+ else {
+ System.out.println(num + " is an odd number.");
+ }
+
+ // Close the scanner to prevent resource leaks
+ sc.close();
+}
diff --git a/FIRST_java_Q3.java b/FIRST_java_Q3.java
new file mode 100644
index 000000000..75f4e1023
--- /dev/null
+++ b/FIRST_java_Q3.java
@@ -0,0 +1,29 @@
+// Write a program to input principal, time, and rate (P, T, R) from the user and
+//find Simple Interest.
+
+import java.util.Scanner;
+
+public class FIRST_java_Q3 {
+ public static void main(String[] args) {
+ Scanner scanner = new Scanner(System.in);
+
+ // Input principal, time, and rate
+ System.out.print("Enter principal (P): ");
+ double principal = scanner.nextDouble();
+
+ System.out.print("Enter time in years (T): ");
+ double time = scanner.nextDouble();
+
+ System.out.print("Enter rate of interest (R): ");
+ double rate = scanner.nextDouble();
+
+ // Calculate Simple Interest
+ double simpleInterest = (principal * time * rate) / 100;
+
+ // Output the result
+ System.out.printf("Simple Interest is: %.2f%n", simpleInterest);
+
+ // Close the scanner
+ scanner.close();
+ }
+}
\ No newline at end of file
diff --git a/FIRST_java_Q4.java b/FIRST_java_Q4.java
new file mode 100644
index 000000000..f45a5da69
--- /dev/null
+++ b/FIRST_java_Q4.java
@@ -0,0 +1,53 @@
+ //Take in two numbers and an operator (+, -, *, /) and calculate the value.
+//(Use if conditions)
+import java.util.Scanner;
+
+public class FIRST_java_Q4 {
+ public static void main(String[] args) {
+ Scanner scanner = new Scanner(System.in);
+
+ // Input first number
+ System.out.print("Enter first number: ");
+ double num1 = scanner.nextDouble();
+
+ // Input second number
+ System.out.print("Enter second number: ");
+ double num2 = scanner.nextDouble();
+
+ // Input operator
+ System.out.print("Enter operator (+, -, *, /): ");
+ char operator = scanner.next().charAt(0);
+
+ double result;
+
+ // Perform calculation based on the operator
+ if (operator == '+') {
+ result = num1 + num2;
+ }
+ else if (operator == '-') {
+ result = num1 - num2;
+ }
+ else if (operator == '*') {
+ result = num1 * num2;
+ }
+ else if (operator == '/') {
+ if (num2 != 0) {
+ result = num1 / num2;
+ } else {
+ System.out.println("Error: Division by zero is not allowed.");
+ scanner.close();
+ return;
+ }
+ } else {
+ System.out.println("Error: Invalid operator.");
+ scanner.close();
+ return;
+ }
+
+ // Output the result
+ System.out.printf("Result: %.2f%n", result);
+
+ // Close the scanner
+ scanner.close();
+ }
+}
diff --git a/FIRSTjava-Q2.java b/FIRSTjava-Q2.java
new file mode 100644
index 000000000..5b544aeb0
--- /dev/null
+++ b/FIRSTjava-Q2.java
@@ -0,0 +1,14 @@
+// Take name as input and print a greeting message for that particular name.
+class Q2
+{
+ public static void main(String[] args) {
+ java.util.Scanner sc = new java.util.Scanner(System.in);
+ System.out.print("Enter your name: ");
+ String name = sc.nextLine();
+
+ System.out.println("Hello, " + name + "! Welcome to the program.");
+
+ // Close the scanner to prevent resource leaks
+ sc.close();
+ }
+}
diff --git a/FLOW_Q3_Krish.java b/FLOW_Q3_Krish.java
new file mode 100644
index 000000000..cc3bbe5c9
--- /dev/null
+++ b/FLOW_Q3_Krish.java
@@ -0,0 +1,18 @@
+// Take a number as input and print the multiplication table for it.
+class FLOW_Q3_Krish
+{
+ public static void main(String[] args)
+ {
+ java.util.Scanner sc = new java.util.Scanner(System.in);
+ System.out.print("Enter a number to print its multiplication table: ");
+ int num = sc.nextInt();
+
+ System.out.println("Multiplication table for " + num + ":");
+ for (int i = 1; i <= 10; i++) {
+ System.out.println(num + " x " + i + " = " + (num * i));
+ }
+ //
+ // Close the scanner to prevent resource leaks
+ sc.close();
+ }
+}
diff --git a/FLOW_Q4_Krish.java b/FLOW_Q4_Krish.java
new file mode 100644
index 000000000..42806b121
--- /dev/null
+++ b/FLOW_Q4_Krish.java
@@ -0,0 +1,30 @@
+// Take 2 numbers as inputs and find their HCF and LCM.
+public class FLOW_Q4_Krish
+{
+ public static void main(String[] args)
+ {
+ java.util.Scanner sc = new java.util.Scanner(System.in);
+ System.out.print("Enter first number: ");
+ int num1 = sc.nextInt();
+ System.out.print("Enter second number: ");
+ int num2 = sc.nextInt();
+
+ int hcf = findHCF(num1, num2);
+ int lcm = (num1 * num2) / hcf;
+
+ System.out.println("HCF of " + num1 + " and " + num2 + " is: " + hcf);
+ System.out.println("LCM of " + num1 + " and " + num2 + " is: " + lcm);
+
+ // Close the scanner to prevent resource leaks
+ sc.close();
+ }
+
+ private static int findHCF(int a, int b) {
+ while (b != 0) {
+ int temp = b;
+ b = a % b;
+ a = temp;
+ }
+ return a;
+ }
+}
diff --git a/FLOW_Q5_Krish.java b/FLOW_Q5_Krish.java
new file mode 100644
index 000000000..c6a8d37a6
--- /dev/null
+++ b/FLOW_Q5_Krish.java
@@ -0,0 +1,29 @@
+//Keep taking numbers as inputs till the user enters ‘x’, after that print sum of all.
+public class FLOW_Q5_Krish
+{
+ public static void main(String[] args)
+ {
+ java.util.Scanner sc = new java.util.Scanner(System.in);
+ int sum = 0;
+ String input;
+
+ System.out.println("Enter numbers to sum them up. Type 'x' to finish:");
+ while (true) {
+ input = sc.nextLine();
+ if (input.equalsIgnoreCase("x")) {
+ break;
+ }
+ try {
+ int num = Integer.parseInt(input);
+ sum += num;
+ } catch (NumberFormatException e) {
+ System.out.println("Invalid input, please enter a number or 'x' to exit.");
+ }
+ }
+
+ System.out.println("The total sum is: " + sum);
+
+ // Close the scanner to prevent resource leaks
+ sc.close();
+ }
+}
diff --git a/FLow_Q2_Krish .java b/FLow_Q2_Krish .java
new file mode 100644
index 000000000..976b0800a
--- /dev/null
+++ b/FLow_Q2_Krish .java
@@ -0,0 +1,18 @@
+// Take two numbers and print the sum of both.
+import java.util.Scanner;
+class FLow_Q2_Krish
+{
+ public static void main(String[] args)
+ {
+ Scanner sc = new Scanner(System.in);
+ System.out.print("Enter first number: ");
+ int num1 = sc.nextInt();
+ System.out.print("Enter second number: ");
+ int num2 = sc.nextInt();
+
+ int sum = num1 + num2;
+ System.out.println("The sum of " + num1 + " and " + num2 + " is: " + sum);
+ // Close the scanner to prevent resource leaks
+ sc.close();
+ }
+}
diff --git a/lectures/20-trees/code/AVL/.project b/lectures/20-trees/code/AVL/.project
index a2380fe36..b545323bf 100644
--- a/lectures/20-trees/code/AVL/.project
+++ b/lectures/20-trees/code/AVL/.project
@@ -22,12 +22,12 @@
- 1679078569810
+ 1752678436405
30
org.eclipse.core.resources.regexFilterMatcher
- node_modules|.git|__CREATED_BY_JAVA_LANGUAGE_SERVER__
+ node_modules|\.git|__CREATED_BY_JAVA_LANGUAGE_SERVER__
diff --git a/lectures/20-trees/code/Questions/.project b/lectures/20-trees/code/Questions/.project
index a2380fe36..a73354206 100644
--- a/lectures/20-trees/code/Questions/.project
+++ b/lectures/20-trees/code/Questions/.project
@@ -22,12 +22,12 @@
- 1679078569810
+ 1752678436432
30
org.eclipse.core.resources.regexFilterMatcher
- node_modules|.git|__CREATED_BY_JAVA_LANGUAGE_SERVER__
+ node_modules|\.git|__CREATED_BY_JAVA_LANGUAGE_SERVER__