C# Sharp Basic Declarations and Expressions : Exercises, Practice, Solution

C# Sharp Basic Exercises [92 exercises with solution]

[An editor is available at the bottom of the page to write and execute the scripts.]

1. Write a C# Sharp program to print Hello and your name in a separate line. Go to the editor
Expected Output :
Hello: Alexandra Abramov
Click me to see the solution

2. Write a C# Sharp program to print the sum of two numbers. Go to the editor
Click me to see the solution

3. Write a C# Sharp program to print the result of dividing two numbers. Go to the editor
Click me to see the solution

4. Write a C# Sharp program to print the result of the specified operations. Go to the editor
Test data:

• -1 + 4 * 6
• ( 35+ 5 ) % 7
• 14 + -4 * 6 / 11
• 2 + 15 / 6 * 1 - 7 % 2

Expected Output:
23
5
12
3
Click me to see the solution

5. Write a C# Sharp program to swap two numbers. Go to the editor
Test Data:
Input the First Number : 5
Input the Second Number : 6
Expected Output:
After Swapping :
First Number : 6
Second Number : 5
Click me to see the solution

6. Write a C# Sharp program to print the output of multiplication of three numbers which will be entered by the user. Go to the editor
Test Data:
Input the first number to multiply: 2
Input the second number to multiply: 3
Input the third number to multiply: 6
Expected Output:
2 x 3 x 6 = 36
Click me to see the solution

7. Write a C# Sharp program to print on screen the output of adding, subtracting, multiplying and dividing of two numbers which will be entered by the user. Go to the editor
Test Data:
Input the first number: 25
Input the second number: 4
Expected Output:
25 + 4 = 29
25 - 4 = 21
25 x 4 = 100
25 / 4 = 6
25 mod 4 = 1
Click me to see the solution

8. Write a C# Sharp program that takes a number as input and print its multiplication table. Go to the editor
Test Data:
Enter the number: 5
Expected Output:
5 * 0 = 0
5 * 1 = 5
5 * 2 = 10
5 * 3 = 15
....
5 * 10 = 50
Click me to see the solution

9. Write a C# Sharp program that takes four numbers as input to calculate and print the average. Go to the editor
Test Data:
Enter the First number: 10
Enter the Second number: 15
Enter the third number: 20
Enter the four number: 30

Expected Output:
The average of 10 , 15 , 20 , 30 is: 18
Click me to see the solution

10. Write a C# Sharp program to that takes three numbers(x,y,z) as input and print the output of (x+y).z and x.y + y.z. Go to the editor
Test Data:
Enter first number - 5
Enter second number - 6
Enter third number - 7

Expected Output:
Result of specified numbers 5, 6 and 7, (x+y).z is 77 and x.y + y.z is 72
Click me to see the solution

11. Write a C# Sharp program that takes an age (for example 20) as input and prints something as "You look older than 20". Go to the editor
Test Data:
Enter your age - 25
Expected Output:
You look older than 25
Click me to see the solution

12. Write a C# program to that takes a number as input and display it four times in a row (separated by blank spaces), and then four times in the next row, with no separation. You should do it two times: Use Console. Write and then use {0}. Go to the editor
Test Data:
Enter a digit: 25
Expected Output:
25 25 25 25
25252525
25 25 25 25
25252525
Click me to see the solution

13. Write a C# program that takes a number as input and then displays a rectangle of 3 columns wide and 5 rows tall using that digit. Go to the editor
Test Data:
Enter a number: 5
Expected Output:
555
5 5
5 5
5 5
555
Click me to see the solution

14. Write a C# program to convert from celsius degrees to Kelvin and Fahrenheit. Go to the editor
Test Data:
Enter the amount of celsius: 30
Expected Output:
Kelvin = 303
Fahrenheit = 86
Click me to see the solution

15. Write a C# program remove specified a character from a non-empty string using index of a character. Go to the editor
Test Data:
w3resource
Sample Output:
wresource
w3resourc
3resource
Click me to see the solution

16. Write a C# program to create a new string from a given string where the first and last characters will change their positions. Go to the editor
Test Data:
w3resource
Python
Sample Output:
e3resourcw
nythoP
x
Click me to see the solution

17. Write a C# program to create a new string from a given string (length 1 or more ) with the first character added at the front and back. Go to the editor
Sample Output:
Input a string : The quick brown fox jumps over the lazy dog.
TThe quick brown fox jumps over the lazy dog.T
Click me to see the solution

18. Write a C# program to check two given integers and return true if one is negative and one is positive. Go to the editor
Sample Output:
Input first integer:
-5
Input second integer:
25
Check if one is negative and one is positive:
True
Click me to see the solution

19. Write a C# program to compute the sum of two given integers, if two values are equal then return the triple of their sum. Go to the editor
Click me to see the solution

20. Write a C# program to get the absolute value of the difference between two given numbers. Return double the absolute value of the difference if the first number is greater than second number. Go to the editor
Click me to see the solution

21. Write a C# program to check the sum of the two given integers and return true if one of the integer is 20 or if their sum is 20. Go to the editor
Click me to see the solution

22. Write a C# program to check if an given integer is within 20 of 100 or 200. Go to the editor
Sample Output:
Input an integer:
25
False
Click me to see the solution

23. Write a C# program to convert a given string into lowercase. Go to the editor
Sample Output:
write a c# sharp program to display the following pattern using the alphabet.
Click me to see the solution

24. Write a C# program to find the longest word in a string. Go to the editor
Test Data: Write a C# Sharp Program to display the following pattern using the alphabet.
Sample Output:
following
Click me to see the solution

25. Write a C# program to print the odd numbers from 1 to 99. Prints one number per line. Go to the editor
Sample Output:
Odd numbers from 1 to 99. Prints one number per line.
1
3
5
7
9
...
95
97
99
Click me to see the solution

26. Write a C# program to compute the sum of the first 500 prime numbers. Go to the editor
Sample Output:
Sum of the first 500 prime numbers:
824693
Click me to see the solution

27. Write a C# program and compute the sum of the digits of an integer. Go to the editor
Sample Output:
Input a number(integer): 12
Sum of the digits of the said integer: 3
Click me to see the solution

28. Write a C# program to reverse the words of a sentence. Go to the editor
Sample Output:
Original String: Display the pattern like pyramid using the alphabet.
Reverse String: alphabet. the using pyramid like pattern the Display
Click me to see the solution

29. Write a C# program to find the size of a specified file in bytes. Go to the editor
Sample Output:
Size of a file: 31
Click me to see the solution

30. Write a C# program to convert a hexadecimal number to decimal number. Go to the editor
Sample Output:
Hexadecimal number: 4B0
Convert to-
Decimal number: 1200
Click me to see the solution

31. Write a C# program to multiply corresponding elements of two arrays of integers. Go to the editor
Sample Output:
Array1: [1, 3, -5, 4]
Array2: [1, 4, -5, -2]
Multiply corresponding elements of two arrays:
1 12 25 -8
Click me to see the solution

32. Write a C# program to create a new string of four copies, taking last four characters from a given string. If the length of the given string is less than 4 return the original one. Go to the editor
Sample Output:
Input a string : The quick brown fox jumps over the lazy dog.
dog.dog.dog.dog.
Click me to see the solution

33. Write a C# program to check if a given positive number is a multiple of 3 or a multiple of 7. Go to the editor
Sample Output:
Input first integer:
15
True
Click me to see the solution

34. Write a C# program to check if a string starts with a specified word. Go to the editor
Note: Suppose the sentence starts with "Hello"
Sample Data: string1 = "Hello how are you?"
Result: Hello.
Sample Output:
Input a string : Hello how are you?
True
Click me to see the solution

35. Write a C# program to check two given numbers where one is less than 100 and other is greater than 200. Go to the editor
Sample Output:
Input a first number(<100): 75
Input a second number(>100): 250
True
Click me to see the solution

36. Write a C# program to check if an integer (from the two given integers) is in the range -10 to 10. Go to the editor
Sample Output:
Input a first number: -5
Input a second number: 8
True
Click me to see the solution

37. Write a C# program to check if "HP" appears at second position in a string and returns the string without "HP". Go to the editor
Test Data: PHP Tutorial
Sample Output:
P Tutorial
Click me to see the solution

38. Write a C# program to get a new string of two characters from a given string. The first and second character of the given string must be "P" and "H", so PHP will be "PH". Go to the editor
Test Data: PHP
Sample Output:
PH
Click me to see the solution

39. Write a C# program to find the largest and lowest values from three integer values. Go to the editor
Test Data:
Input first integer:
15
Input second integer:
25
Input third integer:
30
Sample Output
Largest of three: 30
Lowest of three: 15
Click me to see the solution

40. Write a C# program to check the nearest value of 20 of two given integers and return 0 if two numbers are same. Go to the editor
Test Data:
Input first integer:
15
Input second integer:
12
Sample Output
15
Click me to see the solution

41. Write a C# program to check if a given string contains ‘w’ character between 1 and 3 times. Go to the editor
Test Data:
Input a string (contains at least one 'w' char) : w3resource
Test the string contains 'w' character between 1 and 3 times:
Sample Output
True
Click me to see the solution

42. Write a C# program to create a new string where the first 4 characters will be in lower case. If the string is less than 4 characters then make the whole string in upper case. Go to the editor
Test Data:
Input a string: w3r
Sample Output
W3R
Click me to see the solution

43. Write a C# program to check if a given string starts with "w" and immediately followed by two "ww". Go to the editor
Test Data:
Input a string : www
Sample Output
False
Click me to see the solution

44. Write a C# program to create a new string of every other character (odd position) from the first position of a given string. Go to the editor
Test Data:
Input a string : w3resource
Sample Output
wrsuc
Click me to see the solution

45. Write a C# program to count a specified number in a given array of integers. Go to the editor
Test Data:
Input an integer: 5
Sample Output
Number of 5 present in the said array: 2
Click me to see the solution

46. Write a C# program to check if a number appears as either the first or last element of an array of integers and the length is 1 or more. Go to the editor
Test Data:
Input an integer: 25
Sample Output
False
Click me to see the solution

47. Write a C# program to compute the sum of all the elements of an array of integers. Go to the editor
Test Data:
Array1: [1, 2, 2, 3, 3, 4, 5, 6, 5, 7, 7, 7, 8, 8, 1]
Sample Output
Sum: 69
Click me to see the solution

48. Write a C# program to check if the first element and the last element are equal of an array of integers and the length is 1 or more. Go to the editor
Test Data:
Array1: [1, 2, 2, 3, 3, 4, 5, 6, 5, 7, 7, 7, 8, 8, 1]
Sample Output
True
Click me to see the solution

49. Write a C# program to check if the first element or the last element of the two arrays ( length 1 or more) are equal. Go to the editor
Test Data:
Array1: [1, 2, 2, 3, 3, 4, 5, 6, 5, 7, 7, 7, 8, 8, 1]
Array2: [1, 2, 2, 3, 3, 4, 5, 6, 5, 7, 7, 7, 8, 8, 5]
Check if the first element or the last element of the two arrays ( leng th 1 or more) are equal.
Sample Output
True
Click me to see the solution

50. Write a C# program to rotate an array (length 3) of integers in left direction. Go to the editor
Test Data:
Array1: [1, 2, 8]
After rotating array becomes: [2, 8, 1]
Click me to see the solution

51. Write a C# program to get the larger value between first and last element of an array (length 3) of integers. Go to the editor
Test Data:
Array1: [1, 2, 5, 7, 8]
Highest value between first and last values of the said array: 8
Click me to see the solution

52. Write a C# program to create a new array of length containing the middle elements of three arrays (each length 3) of integers. Go to the editor
Test Data:
Array1: [1, 2, 5]
Array2: [0, 3, 8]
Array3: [-1, 0, 2]
New array: [2, 3, 0]
Click me to see the solution

53. Write a C# program to check if an array contains an odd number. Go to the editor
Test Data:
Original array: [2, 4, 7, 8, 6]
Check if an array contains an odd number? True
Click me to see the solution

54. Write a C# program to get the century from a year. Go to the editor
Click me to see the solution

55. Write a C# program to find the pair of adjacent elements that has the largest product of an given array which is equal to a given value. Go to the editor
Click me to see the solution

56. Write a C# program to check if a given string is a palindrome or not. Go to the editor
Sample Example:
For 'aaa' the output should be true
For 'abcd' the output should be false
Click me to see the solution

57. Write a C# program to find the pair of adjacent elements that has the highest product of an given array of integers. Go to the editor
Click me to see the solution

58. Write a C# program which will accept a list of integers and checks how many integers are needed to complete the range. Go to the editor
Sample Example [1, 3, 4, 7, 9], between 1-9 -> 2, 5, 6, 8 are not present in the list. So output will be 4.
Click me to see the solution

59. Write a C# program to check whether it is possible to create a strictly increasing sequence from a given sequence of integers as an array. Go to the editor
Click me to see the solution

60. Write a C# program to calculate the sum of all the integers of a rectangular matrix except those integers which are located below an intger of value 0. Go to the editor
Sample Example:
matrix = [[0, 2, 3, 2],
[0, 6, 0, 1],
[4, 0, 3, 0]]
Eligible integers which will be participated to calculate the sum -
matrix = [[X, 2, 3, 2],
[X, 6, X, 1],
[X, X, X, X]]
Therefore sum will be: 2 + 3 + 2 + 6 + 1 = 14
Click me to see the solution

61. Write a C# program to sort the integers in ascending order without moving the number -5. Go to the editor
Click me to see the solution

62. Write a C# program to reverse the strings contained in each pair of matching parentheses in a given string and also remove the parentheses within the given string. Go to the editor
Click me to see the solution

63. Write a C# program to check if a given number present in an array of numbers. Go to the editor
Click me to see the solution

64. Write a C# Sharp program to get the file name (including extension) from a given path. Go to the editor
Click me to see the solution

65. Write a C# Sharp program to multiply all of elements of a given array of numbers by the array length. Go to the editor
Click me to see the solution

66. Write a C# Sharp program to find the minimum value from two given two numbers, represented as string. Go to the editor
Click me to see the solution

67. Write a C# Sharp program to create a coded string from a given string, using specified formula. Go to the editor
Replace all 'P' with '9', 'T' with '0', 'S' with '1', 'H' with '6' and 'A' with '8'.
Sample Output:
969
J8V81CRI90
Click me to see the solution

68. Write a C# Sharp program to count a specified character (both cases) in a given string. Go to the editor
Click me to see the solution

69. Write a C# Sharp program to check if a given string contains only lowercase or uppercase characters. Go to the editor
Click me to see the solution

70. Write a C# Sharp program to remove the first and last elements from a given string. Go to the editor
Sample Output:
Original string: PHP
After removing first and last elements: H
Original string: Python
After removing first and last elements: ytho
Original string: JavaScript
After removing first and last elements: avaScrip
Click me to see the solution

71. Write a C# Sharp program to check if a given string contains two similar consecutive letters. Go to the editor
Sample Output:
Original string: PHP
Test for consecutive similar letters! False
Original string: PHHP
Test for consecutive similar letters! True
Original string: PHPP
Test for consecutive similar letters! True
Original string: PPHP
Test for consecutive similar letters! True
Click me to see the solution

72. Write a C# Sharp program to check whether the average value of the elements of a given array of numbers is a whole number or not. Go to the editor
Sample Output:
nums = { 1, 2, 3, 5, 4, 2, 3, 4 }
Check the average value of the said array is a whole number or not: True
nums1 = { 2, 4, 2, 6, 4, 8 }
Check the average value of the said array is a whole number or not: False
Click me to see the solution

73. Write a C# Sharp program to convert the letters of a given string (same case-upper/lower) into alphabetical order. Go to the editor
Sample Output:
Original string: PHP
Convert the letters of the said string into alphabetical order: HPP
Original string: javascript
Convert the letters of the said string into alphabetical order: aacijprstv
Original string: python
Convert the letters of the said string into alphabetical order: hnopty
Click me to see the solution

74. Write a C# Sharp program to check the length of a given string is odd or even. Return 'Odd length' if the string length is odd otherwise 'Even length'. Go to the editor
Sample Output:
Original string: PHP
Convert the letters of the said string into alphabetical order: Odd length
Original string: javascript
Convert the letters of the said string into alphabetical order: Even length
Original string: python
Convert the letters of the said string into alphabetical order: Even length
Click me to see the solution

75. Write a C# Sharp program which takes a positive number and return the nth odd number. Go to the editor
Sample Output:
1st odd number: 1
2nd odd number: 3
4th odd number: 7
100th odd number: 199
Click me to see the solution

76. Write a C# Sharp program to get the ASCII value of a given character. Go to the editor
Sample Output:
Ascii value of 1 is: 49
Ascii value of A is: 65
Ascii value of a is: 97
Ascii value of # is: 35
Click me to see the solution

77. Write a C# Sharp program to check whether a given word is plural or not. Go to the editor
Sample Output:
Is 'Exercise' is plural? False
Is 'Exercises' is plural? True
Is 'Books' is plural? True
Is 'Book' is plural? False
Click me to see the solution

78. Write a C# Sharp program to find sum of squares of elements of a given array of integers. Go to the editor
Sample Output:
Sum of squares of elements of the said array: 14
Sum of squares of elements of the said array: 29
Click me to see the solution

79. Write a C# Sharp program to convert an integer to string and a string to an integer. Go to the editor
Sample Output:
Original value and type: 50, System.String
Convert string to integer:
Return value and type: 50, System.Int32
Original value and type: 122, System.Int32
Convert integer to string:
Return value and type: 122, System.String
Click me to see the solution

80. Write a C# Sharp program to convert all the values of a given array of mixed values to string values. Go to the editor
Sample Output:
Printing original array elements and their types:
Value-> 25 :: Type-> System.Int32
Value-> Anna :: Type-> System.String
Value-> False :: Type-> System.Boolean
Value-> 4/15/2021 10:37:47 AM :: Type-> System.DateTime
Value-> 112.22 :: Type-> System.Double
Printing array elements and their types:
Value-> 25 :: Type-> System.String
Value-> Anna :: Type-> System.String
Value-> False :: Type-> System.String
Value-> 4/15/2021 10:37:47 AM :: Type-> System.String
Value-> 112.22 :: Type-> System.String
Click me to see the solution

81. Write a C# Sharp program to swap a two digit given number and check whether the given number is greater than its swap value. Go to the editor
Sample Output:
Input an integer value:
Check whether the said value is greater than its swap value: True
Click me to see the solution

82. Write a C# Sharp program to remove all characters which are non-letters from a given string. Go to the editor
From Wikipedia,
A letter is a segmental symbol of a phonemic writing system. The inventory of all letters forms the alphabet. Letters broadly correspond to phonemes in the spoken form of the language, although there is rarely a consistent, exact correspondence between letters and phonemes
Sample Output:
Orginal string: [email protected]
Remove all characters from the said string which are non-letters: Python
Orginal string: Python 3.0
Remove all characters from the said string which are non-letters: Python
Orginal string: 2^sdfds*^*^jlljdslfnoswje34u230sdfds984
Remove all characters from the said string which are non-letters: sdfdsjlljdslfnoswjeusdfds
Click me to see the solution

83. Write a C# Sharp program to remove all vowels from a given string. Go to the editor
Sample Output:
Orginal string: Python
After removing all the vowels from the said string: Pythn
Orginal string: C Sharp
After removing all the vowels from the said string: C Shrp
Orginal string: JavaScript
After removing all the vowels from the said string: JvScrpt
Click me to see the solution

84. Write a C# Sharp program to get the index number of all lower case letters in a given string. Go to the editor
Sample Output:
Orginal string: Python
Indices of all lower case letters of the said string:
1 2 3 4 5
Orginal string: JavaScript
Indices of all lower case letters of the said string:
1 2 3 5 6 7 8 9
Click me to see the solution

85. Write a C# Sharp program to find the cumulative sum of an array of number. Go to the editor
A cumulative sum is a sequence of partial sums of a given sequence. For example, the cumulative sums of the sequence {x, y, z,...}, are x , x+y , x+y+z
Sample Output:
Orginal Array elements:
1 3 4 5 6 7
Cumulative sum of the said array elements:
1 4 8 13 19 26
Orginal Array elements:
1.2 -3 4.1 6 -5.47
Cumulative sum of the said array elements:
1.2 -1.8 2.3 8.3 2.83
Click me to see the solution

86. Write a C# Sharp program to get the number of letters and digits in a given string. Go to the editor
Sample Output:
Original string:: Python 3.0
Number of letters: 6 Number of digits: 2
Original string:: dsfkaso230samdm2423sa
Number of letters: 14 Number of digits: 7
Click me to see the solution

87. Write a C# Sharp program to reverse a boolean value. Go to the editor
Sample Output:
Original value: False
Reverse value: True
Original value: True
Reverse value: False
Click me to see the solution

88. Write a C# Sharp program to find the sum of the interior angles (in degrees) of a given Polygon. Input number of straight line(s). Go to the editor
From Wikipedia,
In geometry, a polygon is a plane figure that is described by a finite number of straight line segments connected to form a closed polygonal chain or polygonal circuit. The solid plane region, the bounding circuit, or the two together, may be called a Polygon.
Sample Output:
Input number of straight lines of the polygon:
Sum of the interior angles (in degrees) of the said polygon: -360
Click me to see the solution

89. Write a C# Sharp program to count positive and negative numbers in a given array of integers. Go to the editor
Sample Output:
Original Array elements:
10 -11 12 -13 14 -18 19 -20
Number of positive numbers: 4
Number of negative numbers: 4
Original Array elements:
-4 -3 -2 0 3 5 6 2 6
Number of positive numbers: 5
Number of negative numbers: 3
Original Array elements:
Number of positive numbers: 0
Number of negative numbers: 0
Click me to see the solution

90. Write a C# Sharp program to count number of ones and zeros in the binary representation of a given integer. Go to the editor
Sample Output:
Original number: 12
Number of ones and zeros in the binary representation of the said number:
Number of ones: 2
Number of zeros: 2
Original number: 1234
Number of ones and zeros in the binary representation of the said number:
Number of ones: 5
Number of zeros: 6
Click me to see the solution

91. Write a C# Sharp program to remove all the values except integer values from a given array of mixed values. Go to the editor
Sample Output:
Original array elements:
25 Anna False 4/24/2021 11:43:11 AM -112 -34.67
After removing all the values except integer values from the said array of mixed values: 25 -112
Click me to see the solution

92. Write a C# Sharp program to find the next prime number of a given number. If the given number is a prime number, return the number. Go to the editor
From Wikipedia,
A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only ways of writing it as a product, 1 × 5 or 5 × 1, involve 5 itself. However, 4 is composite because it is a product (2 × 2) in which both numbers are smaller than 4. Primes are central in number theory because of the fundamental theorem of arithmetic: every natural number greater than 1 is either a prime itself or can be factorized as a product of primes that is unique up to their order.
Sample Output:
Original number: 120
Next prime number/Current prime number: 127
Original number: 321
Next prime number/Current prime number: 331
Original number: 43
Next prime number/Current prime number: 43
Original number: 4433
Next prime number/Current prime number: 4441
Click me to see the solution

C# Sharp Code Editor:

More to Come !

Do not submit any solution of the above exercises at here, if you want to contribute go to the appropriate exercise page.