Logic Building Assignment (Java)

Problems on Various Topics

Class and Objects

1.Create a class Student with properties name, age, and grade. Write a program to create an object of Student and display its properties.

• Expected Output:
• Name: John Age: 20 Grade: A

2.Create a class Rectangle with properties length and width. Write a method calculateArea to calculate the area of the rectangle. Create an object of Rectangle, set its properties, and display the area.

• Expected Output:
  Length: 5 Width: 3 Area: 15

3. Create a class Circle with a property radius and a method calculateCircumference to calculate the circumference. Create an object of Circle, set its properties, and display the circumference.

• Expected Output:
  Radius: 7 Circumference: 43.96

4. Create a class Book with properties title, author, and price. Write a program to create an object of Book and display its properties.

• Expected Output:
  Title: Java Programming Author: James Gosling Price: 499

5. Create a class Car with properties model, year, and price. Write a program to create an object of Car and display its properties.

• Expected Output:
  Model: Tesla Model 3 Year: 2020 Price: 35000

Variables and Data Types

6. Write a program to declare variables of different data types (int, float, double, char, boolean) and initialize them. Print the values of these variables.

• Expected Output:
  Integer: 10 Float: 5.75 Double: 19.99 Character: A Boolean: true

7. Write a program to swap two variables without using a third variable.

• Input: a = 5, b = 3
• Expected Output:
  After swapping: a = 3, b = 5

8. Write a program to demonstrate the use of type casting in Java. Convert a double to an int and print both values.

• Input: doubleValue = 10.99
• Expected Output:
  Double value: 10.99 Integer value: 10

9. Write a program to demonstrate the use of constants in Java. Declare a constant PI with the value 3.14 and use it to calculate the area of a circle.

• Input: radius = 5
• Expected Output:
  Area of the circle: 78.5

Pattern Matching

10. Write a program to print the following pattern:
    • Pattern:
    * * * * * * * * * * * * * * *
    • Expected Output:
    * * * * * * * * * * * * * * *
11. Write a program to print the following pattern:
    • Pattern:
    1 1 2 1 2 3 1 2 3 4 1 2 3 4 5
    • Expected Output:
    1 1 2 1 2 3 1 2 3 4 1 2 3 4 5
12. Write a program to print the following pattern:
    • Pattern:
    A A B A B C A B C D A B C D E
    • Expected Output:
    A A B A B C A B C D A B C D E
13. Write a program to print the following pattern:
    • Pattern:
    1 2 3 4 5 6 7 8 9 10
    • Expected Output:
    1 2 3 4 5 6 7 8 9 10
14. Write a program to print the following pattern:
    • Pattern:
    5 4 3 2 1 4 3 2 1 3 2 1 2 1 1
    • Expected Output:
    5 4 3 2 1 4 3 2 1 3 2 1 2 1 1
15. Write a program to print the following pattern:
    • Pattern:
      A B C D E F G H I J
    • Expected Output:
      A B C D E F G H I J

Operators

16. Write a program to perform arithmetic operations (addition, subtraction, multiplication, division) on two numbers.
    • Input: a = 10, b = 5
    • Expected Output:
    Addition: 15 Subtraction: 5 Multiplication: 50 Division: 2
17. Write a program to demonstrate the use of relational operators by comparing two numbers.
    • Input: a = 10, b = 5
    • Expected Output:
    a > b: true a < b: false a == b: false a != b: true a >= b: true a <= b: false
18. Write a program to demonstrate the use of logical operators. Check if a number is between 10 and 20 and if it is even.
    • Input: number = 12
    • Expected Output:
    Number is between 10 and 20: true Number is even: true
19. Write a program to demonstrate the use of bitwise operators. Perform AND, OR, and XOR operations on two numbers.
    • Input: a = 6, b = 4
    • Expected Output:
    a & b: 4 a | b: 6 a ^ b: 2
20. Write a program to demonstrate the use of increment and decrement operators.
    • Input: a = 5
    • Expected Output:
      a++: 5 ++a: 7 a--: 7 --a: 5

Conditional Statements

21. Write a program to check if a number is even or odd.
    • Input: number = 7
    • Expected Output:
    7 is odd
22. Write a program to find the largest of three numbers using if-else statements.
    • Input: a = 10, b = 20, c = 15
    • Expected Output:
    Largest number is 20
23. Write a program to check if a year is a leap year.
    • Input: year = 2020
    • Expected Output:
    2020 is a leap year
24. Write a program to determine the grade of a student based on marks obtained.
    • Input: marks = 85
    • Expected Output:
    Grade: A
25. Write a program to find the smallest of four numbers using nested if-else statements.
    • Input: a = 10, b = 20, c = 5, d = 15
    • Expected Output:
    Smallest number is 5
26. Write a program to check if a character is a vowel or consonant.
    • Input: char = 'a'
    • Expected Output:
    a is a vowel
27. Write a program to check if a number is positive, negative, or zero.
    • Input: number = -5
    • Expected Output:
    -5 is negative

Loops

28. Write a program to print the first 10 natural numbers using a for loop.
    • Expected Output:
    1 2 3 4 5 6 7 8 9 10
29. Write a program to calculate the factorial of a number using a while loop.
    • Input: number = 5
    • Expected Output:
    Factorial of 5 is 120
30. Write a program to print all even numbers between 1 and 50 using a for loop.
    • Expected Output:
    2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
31. Write a program to find the sum of all odd numbers between 1 and 100 using a while loop.
    • Expected Output:
    Sum of odd numbers: 2500
32. Write a program to reverse a number using a while loop.
    • Input: number = 12345
    • Expected Output:
    Reversed number: 54321
33. Write a program to print the Fibonacci series up to N terms using a for loop.
    • Input: N = 10
    • Expected Output:
    0 1 1 2 3 5 8 13 21 34
34. Write a program to print the multiplication table of a number using a for loop.
    • Input: number = 5
    • Expected Output:
    5 x 1 = 5 5 x 2 = 10 5 x 3 = 15 5 x 4 = 20 5 x 5 = 25 5 x 6 = 30 5 x 7 = 35 5 x 8 = 40 5 x 9 = 45 5 x 10 = 50
35. Write a program to check if a number is prime using a for loop.
    • Input: number = 29
    • Expected Output:
    29 is a prime number
36. Write a program to find the greatest common divisor (GCD) of two numbers using a while loop.
    • Input: a = 48, b = 18
    • Expected Output:
    GCD: 6
37. Write a program to print the sum of digits of a number using a while loop.
    • Input: number = 1234
    • Expected Output:
      Sum of digits: 10

Arrays

38. Write a program to find the largest element in an array.
    • Input: arr = {10, 20, 30, 40, 50}
    • Expected Output:
    Largest element is 50
39. Write a program to reverse an array.
    • Input: arr = {1, 2, 3, 4, 5}
    • Expected Output:
    Reversed array: {5, 4, 3, 2, 1}
40. Write a program to find the sum of all elements in an array.
    • Input: arr = {1, 2, 3, 4, 5}
    • Expected Output:
    Sum of elements: 15
41. Write a program to find the second largest element in an array.
    • Input: arr = {10, 20, 30, 40, 50}
    • Expected Output:
    Second largest element is 40
42. Write a program to sort an array in ascending order.
    • Input: arr = {5, 3, 8, 1, 2}
    • Expected Output:
    Sorted array: {1, 2, 3, 5, 8}
43. Write a program to merge two arrays into a third array.
    • Input: arr1 = {1, 2, 3}, arr2 = {4, 5, 6}
    • Expected Output:
    Merged array: {1, 2, 3, 4, 5, 6}
44. Write a program to find the common elements between two arrays.
    • Input: arr1 = {1, 2, 3, 4}, arr2 = {3, 4, 5, 6}
    • Expected Output:
    Common elements: {3, 4}
45. Write a program to remove duplicate elements from an array.
    • Input: arr = {1, 2, 2, 3, 4, 4, 5}
    • Expected Output:
    Array without duplicates: {1, 2, 3, 4, 5}
46. Write a program to find the frequency of each element in an array.
    • Input: arr = {1, 2, 2, 3, 3, 3, 4}
    • Expected Output:
      Element 1: 1 time(s) Element 2: 2 time(s) Element 3: 3 time(s) Element 4: 1 time(s)

Strings

47. Write a program to accept a string from the user and print it.
    • Input: My name is John
    • Expected Output:
    My name is John
48. Write a program to accept a string from the user and count the number of vowels in it.
    • Input: Hello World
    • Expected Output:
    Number of vowels: 3
49. Write a program to accept a string from the user and count the number of words in it.
    • Input: Java is fun
    • Expected Output:
    Number of words: 3
50. Write a program to accept a string from the user and reverse it.
    • Input: Hello
    • Expected Output:
    Reversed string: olleH
51. Write a program to accept a string from the user and check if it is a palindrome.
    • Input: level
    • Expected Output:
    The string is a palindrome
52. Write a program to convert a string to uppercase without using library functions.
    • Input: hello
    • Expected Output:
    HELLO
53. Write a program to convert a string to lowercase without using library functions.
    • Input: HELLO
    • Expected Output:
    hello
54. Write a program to find the length of a string without using library functions.
    • Input: Hello
    • Expected Output:
    Length of string: 5
55. Write a program to count the number of uppercase, lowercase, and digits in a string.
    • Input: Abc123
    • Expected Output:
    Uppercase: 1 Lowercase: 2 Digits: 3
56. Write a program to replace all spaces in a string with underscores.
    • Input: Hello World
    • Expected Output:
    Hello_World
57. Write a program to find the first occurrence of a character in a string.
    • Input: Hello World, l
    • Expected Output:
    Character 'l' found at position 2
58. Write a program to find the last occurrence of a character in a string.
    • Input: Hello World, l
    • Expected Output:
    Character 'l' found at position 9
59. Write a program to check if two strings are anagrams.
    • Input: listen, silent
    • Expected Output:
      The strings are anagrams
60. Write a program to declare two integer variables and print their sum.
    • Input: a = 5, b = 10
    • Expected Output:
    Sum: 15
61. Write a program to calculate the area of a circle with a given radius.
    • Input: radius = 7
    • Expected Output:
    Area: 153.93804002589985
62. Write a program to swap two numbers without using a third variable.
    • Input: a = 5, b = 10
    • Expected Output:
    a: 10, b: 5
63. Write a program to find the average of three numbers.
    • Input: a = 5, b = 10, c = 15
    • Expected Output:
      Average: 10.0
64. Write a program to demonstrate the use of arithmetic operators.
    • Input: a = 10, b = 5
    • Expected Output:
    Addition: 15 Subtraction: 5 Multiplication: 50 Division: 2 Modulus: 0
65. Write a program to demonstrate the use of relational operators.
    • Input: a = 10, b = 5
    • Expected Output:
    a > b: true a < b: false a >= b: true a <= b: false a == b: false a != b: true
66. Write a program to demonstrate the use of logical operators.
    • Input: a = true, b = false
    • Expected Output:
    a && b: false a || b: true !a: false
67. Write a program to demonstrate the use of bitwise operators.
    • Input: a = 5, b = 3
    • Expected Output:
      a & b: 1 a | b: 7 a ^ b: 6 ~a: -6 a << 1: 10 a >> 1: 2
68. Write a program to check if a number is even or odd.
    • Input: number = 7
    • Expected Output:
    7 is odd
69. Write a program to find the largest of three numbers.
    • Input: a = 10, b = 15, c = 5
    • Expected Output:
    Largest number is 15
70. Write a program to check if a year is a leap year.
    • Input: year = 2020
    • Expected Output:
    2020 is a leap year
71. Write a program to check if a character is a vowel or consonant.
    • Input: char = 'e'
    • Expected Output:
      e is a vowel
72. Write a program to print the first 10 natural numbers using a for loop.
    • Expected Output:
    1 2 3 4 5 6 7 8 9 10
73. Write a program to calculate the factorial of a number using a while loop.
    • Input: number = 5
    • Expected Output:
    Factorial of 5 is 120
74. Write a program to print all even numbers between 1 and 50 using a for loop.
    • Expected Output:
    2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42 44 46 48 50
75. Write a program to find the sum of all odd numbers between 1 and 100 using a while loop.
    • Expected Output:
    Sum of odd numbers: 2500
76. Write a program to reverse a number using a while loop.
    • Input: number = 12345
    • Expected Output:
    Reversed number: 54321
77. Write a program to print the Fibonacci series up to N terms using a for loop.
    • Input: N = 10
    • Expected Output:
    0 1 1 2 3 5 8 13 21 34
78. Write a program to print the multiplication table of a number using a for loop.
    • Input: number = 5
    • Expected Output:
    5 x 1 = 5 5 x 2 = 10 5 x 3 = 15 5 x 4 = 20 5 x 5 = 25 5 x 6 = 30 5 x 7 = 35 5 x 8 = 40 5 x 9 = 45 5 x 10 = 50
79. Write a program to check if a number is prime using a for loop.
    • Input: number = 29
    • Expected Output:
    29 is a prime number
80. Write a program to find the greatest common divisor (GCD) of two numbers using a while loop.
    • Input: a = 48, b = 18
    • Expected Output:
    GCD: 6
81. Write a program to print the sum of digits of a number using a while loop.
    • Input: number = 1234
    • Expected Output:
      Sum of digits: 10
82. Write a program to find the largest element in an array.
    • Input: arr = {10, 20, 30, 40, 50}
    • Expected Output:
    Largest element is 50
83. Write a program to reverse an array.
    • Input: arr = {1, 2, 3, 4, 5}
    • Expected Output:
    Reversed array: {5, 4, 3, 2, 1}
84. Write a program to find the sum of all elements in an array.
    • Input: arr = {1, 2, 3, 4, 5}
    • Expected Output:
    Sum of elements: 15
85. Write a program to find the second largest element in an array.
    • Input: arr = {10, 20, 30, 40, 50}
    • Expected Output:
    Second largest element is 40
86. Write a program to sort an array in ascending order.
    • Input: arr = {5, 3, 8, 1, 2}
    • Expected Output:
    Sorted array: {1, 2, 3, 5, 8}
87. Write a program to merge two arrays into a third array.
    • Input: arr1 = {1, 2, 3}, arr2 = {4, 5, 6}
    • Expected Output:
    Merged array: {1, 2, 3, 4, 5, 6}
88. Write a program to find the common elements between two arrays.
    • Input: arr1 = {1, 2, 3, 4}, arr2 = {3, 4, 5, 6}
    • Expected Output:
    Common elements: {3, 4}
89. Write a program to remove duplicate elements from an array.
    • Input: arr = {1, 2, 2, 3, 4, 4, 5}
    • Expected Output:
    Array without duplicates: {1, 2, 3, 4, 5}
90. Write a program to find the frequency of each element in an array.
    • Input: `arr = {1, 2, 2, 3, 3,

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Mahesh Wabale

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Mahesh Wabale is the admin & author of this blog, Technology enthusiast with interest in DevOps, CICD, Spring Boot, Microservices Architecture He has more than 7 years of experience in IT industry, programming language and development stuff. He loves to share his experience with his blog.

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