Java Programming Lab-2 Solutions
7 days ago
Java Programming Lab-2 Solutions
Here are the solutions for all 10 programming problems:
1. Multiplication Table
import java.util.Scanner;
public class MultiplicationTable {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter an integer: ");
int num = sc.nextInt();
System.out.println("Multiplication Table of " + num + ":");
for (int i = 1; i <= 10; i++) {
System.out.println(num + " x " + i + " = " + (num * i));
}
sc.close();
}
}Sample Output:
Enter an integer: 5
Multiplication Table of 5:
5 x 1 = 5
5 x 2 = 10
5 x 3 = 15
...
5 x 10 = 502. Natural Numbers up to 100 (using different loops)
(a) Using for loop
public class NaturalNumbersFor {
public static void main(String[] args) {
System.out.println("Natural numbers up to 100 (for loop):");
for (int i = 1; i <= 100; i++) {
System.out.print(i + " ");
}
}
}(b) Using while loop
public class NaturalNumbersWhile {
public static void main(String[] args) {
System.out.println("Natural numbers up to 100 (while loop):");
int i = 1;
while (i <= 100) {
System.out.print(i + " ");
i++;
}
}
}(c) Using do-while loop
public class NaturalNumbersDoWhile {
public static void main(String[] args) {
System.out.println("Natural numbers up to 100 (do-while loop):");
int i = 1;
do {
System.out.print(i + " ");
i++;
} while (i <= 100);
}
}Sample Output (for all three):
1 2 3 4 ... 1003. Display Digits Used in a Number
import java.util.Scanner;
public class DisplayDigits {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number: ");
int num = Math.abs(sc.nextInt()); // Handle negative numbers
System.out.print("Digits used: ");
if (num == 0) {
System.out.print("0");
} else {
boolean[] digitsPresent = new boolean[10];
while (num > 0) {
int digit = num % 10;
digitsPresent[digit] = true;
num /= 10;
}
for (int i = 0; i < 10; i++) {
if (digitsPresent[i]) {
System.out.print(i + " ");
}
}
}
sc.close();
}
}Sample Output:
Enter a number: 1234554321
Digits used: 1 2 3 4 5 4. Count Digits in a Number
import java.util.Scanner;
public class CountDigits {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number: ");
int num = Math.abs(sc.nextInt()); // Handle negative numbers
int count = (num == 0) ? 1 : 0;
while (num > 0) {
count++;
num /= 10;
}
System.out.println("Number of digits: " + count);
sc.close();
}
}Sample Output:
Enter a number: 12345
Number of digits: 55. Reverse a Number
import java.util.Scanner;
public class ReverseNumber {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number: ");
int num = sc.nextInt();
int reversed = 0;
int original = num;
while (num != 0) {
int digit = num % 10;
reversed = reversed * 10 + digit;
num /= 10;
}
System.out.println("Reverse of " + original + " is " + reversed);
sc.close();
}
}Sample Output:
Enter a number: 12345
Reverse of 12345 is 543216. Check Palindrome Number
import java.util.Scanner;
public class PalindromeCheck {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number: ");
int num = sc.nextInt();
int reversed = 0;
int original = num;
while (num != 0) {
int digit = num % 10;
reversed = reversed * 10 + digit;
num /= 10;
}
if (original == reversed) {
System.out.println(original + " is a palindrome");
} else {
System.out.println(original + " is not a palindrome");
}
sc.close();
}
}Sample Output:
Enter a number: 12321
12321 is a palindrome7. Display Day Name
import java.util.Scanner;
public class DayName {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number (1-7): ");
int day = sc.nextInt();
String dayName;
switch (day) {
case 1: dayName = "Sunday"; break;
case 2: dayName = "Monday"; break;
case 3: dayName = "Tuesday"; break;
case 4: dayName = "Wednesday"; break;
case 5: dayName = "Thursday"; break;
case 6: dayName = "Friday"; break;
case 7: dayName = "Saturday"; break;
default: dayName = "Invalid day number";
}
System.out.println("Day: " + dayName);
sc.close();
}
}Sample Output:
Enter a number (1-7): 3
Day: Tuesday8. Arithmetic Operations using Switch
import java.util.Scanner;
public class ArithmeticSwitch {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter first number: ");
double num1 = sc.nextDouble();
System.out.print("Enter second number: ");
double num2 = sc.nextDouble();
System.out.println("Choose operation:");
System.out.println("1. Addition");
System.out.println("2. Subtraction");
System.out.println("3. Multiplication");
System.out.println("4. Division");
System.out.print("Enter choice (1-4): ");
int choice = sc.nextInt();
double result = 0;
switch (choice) {
case 1:
result = num1 + num2;
System.out.println("Sum: " + result);
break;
case 2:
result = num1 - num2;
System.out.println("Difference: " + result);
break;
case 3:
result = num1 * num2;
System.out.println("Product: " + result);
break;
case 4:
if (num2 != 0) {
result = num1 / num2;
System.out.println("Quotient: " + result);
} else {
System.out.println("Cannot divide by zero");
}
break;
default:
System.out.println("Invalid choice");
}
sc.close();
}
}Sample Output:
Enter first number: 10
Enter second number: 5
Choose operation:
1. Addition
2. Subtraction
3. Multiplication
4. Division
Enter choice (1-4): 3
Product: 50.09. Circle Calculations (Area or Circumference)
import java.util.Scanner;
public class CircleCalculations {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter radius of circle: ");
double radius = sc.nextDouble();
System.out.println("Choose calculation:");
System.out.println("1. Area");
System.out.println("2. Circumference");
System.out.print("Enter choice (1-2): ");
int choice = sc.nextInt();
switch (choice) {
case 1:
double area = Math.PI * radius * radius;
System.out.printf("Area: %.2f\n", area);
break;
case 2:
double circumference = 2 * Math.PI * radius;
System.out.printf("Circumference: %.2f\n", circumference);
break;
default:
System.out.println("Invalid choice");
}
sc.close();
}
}Sample Output:
Enter radius of circle: 5
Choose calculation:
1. Area
2. Circumference
Enter choice (1-2): 1
Area: 78.5410. Menu-Based Number Checker
import java.util.Scanner;
public class NumberChecker {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
System.out.print("Enter a number: ");
double num = sc.nextDouble();
System.out.println("Choose check:");
System.out.println("1. Odd/Even");
System.out.println("2. Positive/Negative");
System.out.print("Enter choice (1-2): ");
int choice = sc.nextInt();
switch (choice) {
case 1:
if (num % 2 == 0) {
System.out.println(num + " is even");
} else {
System.out.println(num + " is odd");
}
break;
case 2:
if (num > 0) {
System.out.println(num + " is positive");
} else if (num < 0) {
System.out.println(num + " is negative");
} else {
System.out.println(num + " is zero");
}
break;
default:
System.out.println("Invalid choice");
}
sc.close();
}
}Sample Output:
Enter a number: -7
Choose check:
1. Odd/Even
2. Positive/Negative
Enter choice (1-2): 1
-7.0 is oddEach program includes proper input handling, comments, and follows good coding practices. The programs demonstrate various Java concepts including loops, conditional statements, switch-case, and basic arithmetic operations.