Questions:

Q1: Create a variable age and store your age. Print it.

Q2: Store your name in a variable and print "Hello, [name]!"

Q3: Create two variables a = 10, b = 20, and print their sum.

Q4: Check if a number is positive, negative, or zero.

Q5: Check if someone is eligible to vote (age ≥ 18).

Q6: Given marks, print the grade: A (90+), B (75–89), C (50–74), Fail (<50).

Q7: Ask the user for their name and greet them.

Q8: Take two numbers as input and print the sum.

Q9: Ask the user for their age and check if they can drive (18+).

Q10: Print numbers from 1 to 10.

Q11: Print the sum of numbers from 1 to 100.

Q12: Print all even numbers from 1 to 50.

Q13: Print a square of * of size 5x5.

*****
*****
*****
*****
*****

Q14: Print a right triangle pattern of *:

*
**
***
****
*****

Q16: Create a function greet() that prints "Good Morning!".

Q17: Write a function that takes two numbers and returns their sum.

Q18: Write a function to check if a number is even or odd.

Q19: Create a class with a method sayHello() that prints "Hello from method!".

Q20: Write a method that returns the square of a number.

Q21: Write a method to print whether a number is positive or negative.

Q22: Ask the user to enter a number from 1 to 3:

1 → Print "One"

2 → Print "Two"
3 → Print "Three"

Q23: Ask for a day number (1 to 7) and print the day name using switch.

Q24: Print numbers from 1 to n → What's the time complexity? (O(n))

Q25: Print a 5x5 star pattern → How many total * will print? (25)

Q26: Ask for a number → print whether it’s even/odd → and print that many * using a
loop.
(User Input + Conditional + Loop + Pattern)

Q27: Create a menu using switch:

Say Hello

Print 1–10

Exit
(Switch + Loop + Function)

Answers:

1.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Enter your age: ");
int a = sc.nextInt();
System.out.println(a);

}
}

2.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Enter your name: ");
String a = sc.nextLine();
System.out.println("Hello! " + a);

}
}

3.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
int a = 10;
int b = 20;
int sum = a + b;
 System.out.println(sum);
}
}

4.)
mport java.util.Scanner;

class test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int a = sc.nextInt();
if(a == 0) {
System.out.println("Zero");
} else {
if(a > 0) {
System.out.println("Positive");
} else {
System.out.println("Negative");

}
}

}
}

5.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int a = sc.nextInt();
if(a == 0) {
System.out.println("Invalid");
} else {
if(a < 18) {
System.out.println("Not Eligible");
} else {
System.out.println("Eligible");
}
}

}
}

6.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int a = sc.nextInt();
if(a >= 90) {
System.out.println("A");
} else {
if(a >= 75) {
System.out.println("B");
} else {
if(a >= 50) {
 System.out.println("C");
} else {
System.out.println("D");
}
}
}

}
}

7.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Enter your name: ");
String a = sc.nextLine();
System.out.println("Hello! " + a);

}
}

8.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
int a = 10;
int b = 20;
int sum = a + b;
System.out.println(sum);
}
}

9.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.println("Enter your age: ");
int a = sc.nextInt();
if(a == 0) {
System.out.println("Invalid");
} else {
if(a < 18) {
System.out.println("Cannot Drive");
} else {
System.out.println("Can Drive");
}
}

}
}

10.)
import java.util.Scanner;
class test {
public static void main(String[] args) {
for(int i = 0; i <= 10; i++) {
System.out.println(i);
}

}
}

11.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
int sum = 0;
for(int i = 0; i <= 100; i++) {
sum = sum + i;
System.out.println(sum);
}

}
}

12.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
int sum = 0;
for(int i = 0; i <= 50; i++) {
if(i % 2 == 0) {
sum = sum + i;
System.out.println(sum);
}
}
}
}

13.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
int sum = 0;
for(int i = 1; i <= 5; i++) {
for(int j = 1; j<=5; j++) {
System.out.print("*");
}
System.out.println();

}
}
}

14.)
import java.util.Scanner;
class test {
public static void main(String[] args) {
int sum = 0;
for(int i = 1; i <= 5; i++) {
for(int j = 1; j<=i; j++) {
System.out.print("*");
}
System.out.println();

}
}
}

16.)
import java.util.Scanner;

class test {
public static void greet(String[] args) {
System.out.println("Good Morning");
}
public static void main(String[] args) {
greet(args);

}
}

17.)
import java.util.Scanner;

class test {
public static void greet(int a, int b) {
int sum = a + b;
System.out.println(sum);
}
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int a = sc.nextInt();
int b = sc.nextInt();
greet(a, b);

}
}

18.)
import java.util.Scanner;

class test {
public static void greet(int a) {
if(a % 2 == 0) {
System.out.println("Even");
} else {
System.out.println("Odd");
}
}
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int a = sc.nextInt();
greet(a);
 }
}

19.)
import java.util.Scanner;

class HelloClass {
void sayHello() {
System.out.println("Hello from method!");
}
}

public class test {

public static void main(String[] args) {
HelloClass hello = new HelloClass();
hello.sayHello();
}
}

20.)
import java.util.Scanner;

public class test {

public static void main(String[] args) {
MathUtils math = new MathUtils();
int num = 5;
int result = math.square(num);
System.out.println("Square of " + num + " is: " + result);
}
}

21.)
import java.util.Scanner;

class NumberChecker {
void printSign(int number) {
if (number > 0) {
System.out.println(number + " is positive.");
} else if (number < 0) {
System.out.println(number + " is negative.");
} else {
System.out.println("The number is zero.");
}
}
}

public class test {

public static void main(String[] args) {
NumberChecker checker = new NumberChecker();
checker.printSign(10);
checker.printSign(-5);
checker.printSign(0);
}
}

22.)
import java.util.*;

class test {
 public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int a = sc.nextInt();
if(a == 1) {
System.out.println("One");
}
if(a == 2) {
System.out.println("Two");
}
if(a == 3) {
System.out.println("Three");
} else {
System.out.println("Invalid");
}
}
}

23.)
import java.util.Scanner;

public class test {

public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print("Enter day number (1 to 7): ");
int day = scanner.nextInt();

switch (day) {
case 1:
System.out.println("Sunday");
break;
case 2:
System.out.println("Monday");
break;
case 3:
System.out.println("Tuesday");
break;
case 4:
System.out.println("Wednesday");
break;
case 5:
System.out.println("Thursday");
break;
case 6:
System.out.println("Friday");
break;
case 7:
System.out.println("Saturday");
break;
default:
System.out.println("Invalid day number!");
}
scanner.close();
}
}

24.)
import java.util.Scanner;

public class test {

 public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print("Enter n: ");
int n = scanner.nextInt();

for (int i = 1; i <= n; i++) {

System.out.println(i);
}
}
}

Time Complexity: O(n).

25.)
import java.util.Scanner;

class test {
public static void main(String[] args) {
int sum = 0;
for(int i = 1; i <= 5; i++) {
for(int j = 1; j<=5; j++) {
System.out.print("*");
}
System.out.println();

}
}
}

No of Stars: 25

26.)
import java.util.Scanner;

public class test {

public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);
System.out.print("Enter a number: ");
int n = scanner.nextInt();

if (n % 2 == 0) {
System.out.println(n + " is even.");
} else {
System.out.println(n + " is odd.");
}

for (int i = 0; i < n; i++) {

System.out.print("*");
}
System.out.println();

scanner.close();
}
}

27.)
import java.util.Scanner;

public class test {

 public static void main(String[] args) {
Scanner scanner = new Scanner(System.in);

System.out.println("Menu:");
System.out.println("1. Say Hello");
System.out.println("2. Print 1–10");
System.out.print("Enter your choice: ");
int choice = scanner.nextInt();

switch (choice) {
case 1:
System.out.println("Hello!");
break;
case 2:
for (int i = 1; i <= 10; i++) {
System.out.println(i);
}
break;
default:
System.out.println("Invalid choice.");
}
}
}