
Practice 100 Functions and Control Flow Coding Questions
Q1. Write a Rust program to create and call a simple function that prints "Hello, Rust!".
Input:
None
Expected Output:
Hello, Rust!
Q2. Write a Rust program to create a function that takes two integers as arguments and returns their sum.
Input:
a = 5, b = 10
Expected Output:
Sum: 15
Q3. Write a Rust program to calculate the factorial of a number using a recursive function.
Input:
n = 5
Expected Output:
Factorial: 120
Q4. Write a Rust program to check if a number is even or odd using a function.
Input:
n = 7
Expected Output:
Odd
Q5. Write a Rust program to implement a function that prints the larger of two numbers.
Input:
a = 8, b = 12
Expected Output:
Larger number: 12
Q6. Write a Rust program to demonstrate the use of the if statement to check if a number is positive, negative, or zero.
Input:
n = -5
Expected Output:
Negative
Q7. Write a Rust program to demonstrate a for loop that prints numbers from 1 to 10.
Input:
None
Expected Output:
1 2 3 4 5 6 7 8 9 10
Q8. Write a Rust program to demonstrate the use of a while loop to calculate the sum of numbers from 1 to 5.
Input:
None
Expected Output:
Sum: 15
Q9. Write a Rust program to check if a character is a vowel or consonant using an if statement.
Input:
char = 'a'
Expected Output:
Vowel
Q10. Write a Rust program to demonstrate the use of a match statement to display the day of the week.
Input:
day = 3
Expected Output:
Wednesday
Q11. Write a Rust program to create a function that finds the maximum of three numbers.
Input:
a = 3, b = 5, c = 1
Expected Output:
Maximum: 5
Q12. Write a Rust program to use a for loop to print the elements of an array.
Input:
Array: [2, 4, 6, 8]
Expected Output:
2 4 6 8
Q13. Write a Rust program to demonstrate a break statement within a loop.
Input:
None
Expected Output:
Loop terminated at count = 3
Q14. Write a Rust program to create a function that calculates the square of a number.
Input:
n = 4
Expected Output:
Square: 16
Q15. Write a Rust program to use a match statement to check the grade of a student based on marks.
Input:
marks = 85
Expected Output:
Grade: A
Q16. Write a Rust program to demonstrate an infinite loop using loop and terminate it with a break statement.
Input:
None
Expected Output:
Breaking the infinite loop
Q17. Write a Rust program to implement a function that reverses a string.
Input:
String: "Rust"
Expected Output:
Reversed: "tsuR"
Q18. Write a Rust program to use the continue statement to skip printing even numbers in a loop.
Input:
None
Expected Output:
Odd numbers: 1 3 5 7 9
Q19. Write a Rust program to create a function that returns the absolute value of a number.
Input:
n = -7
Expected Output:
Absolute value: 7
Q20. Write a Rust program to check if a number is divisible by both 3 and 5 using a function.
Input:
n = 15
Expected Output:
Divisible by 3 and 5
Q21. Write a Rust program to demonstrate the use of a default parameter in a function.
Input:
Value provided: None
Expected Output:
Default value: 10
Q22. Write a Rust program to use a for loop to calculate the sum of an array's elements.
Input:
Array: [1, 2, 3, 4, 5]
Expected Output:
Sum: 15
Q23. Write a Rust program to create a function that calculates the power of a number.
Input:
Base = 2, Exponent = 3
Expected Output:
Result: 8
Q24. Write a Rust program to demonstrate nested if statements to check the range of a number.
Input:
n = 15
Expected Output:
The number is between 10 and 20
Q25. Write a Rust program to use a match statement to check the type of a variable.
Input:
Variable: "Rustacean"
Expected Output:
It is a string
Q26. Write a Rust program to demonstrate a countdown from 10 to 1 using a while loop.
Input:
None
Expected Output:
10 9 8 7 6 5 4 3 2 1
Q27. Write a Rust program to implement a function that calculates the greatest common divisor (GCD) of two numbers.
Input:
a = 24, b = 36
Expected Output:
GCD: 12
Q28. Write a Rust program to create a function that checks if a string is a palindrome.
Input:
String: "madam"
Expected Output:
Palindrome: true
Q29. Write a Rust program to use a for loop to print all even numbers from 1 to 20.
Input:
None
Expected Output:
Even numbers: 2 4 6 8 10 12 14 16 18 20
Q30. Write a Rust program to use the match statement to implement a simple calculator.
Input:
Operation: '+', a = 5, b = 3
Expected Output:
Result: 8
Q31. Write a Rust program to create a function that checks if a year is a leap year.
Input:
Year: 2024
Expected Output:
Leap year: true
Q32. Write a Rust program to demonstrate early return from a function using the return keyword.
Input:
Value: 0
Expected Output:
Returned early with value: 0
Q33. Write a Rust program to create a function that returns the smaller of two numbers.
Input:
a = 12, b = 9
Expected Output:
Smaller number: 9
Q34. Write a Rust program to use a while loop to print the Fibonacci sequence up to 10 terms.
Input:
None
Expected Output:
Fibonacci sequence: 0 1 1 2 3 5 8 13 21 34
Q35. Write a Rust program to create a function that reverses an array.
Input:
Array: [1, 2, 3, 4, 5]
Expected Output:
Reversed array: [5, 4, 3, 2, 1]
Q36. Write a Rust program to demonstrate the use of an else if chain.
Input:
Score = 85
Expected Output:
Grade: B
Q37. Write a Rust program to create a function that calculates the sum of digits of a number.
Input:
Number: 1234
Expected Output:
Sum of digits: 10
Q38. Write a Rust program to use a for loop to iterate over a range of numbers.
Input:
Range: 1..6
Expected Output:
1 2 3 4 5
Q39. Write a Rust program to create a function that counts the number of vowels in a string.
Input:
String: "Rustacean"
Expected Output:
Number of vowels: 4
Q40. Write a Rust program to use a match statement to classify numbers as positive, negative, or zero.
Input:
Number: -7
Expected Output:
Negative
Q41. Write a Rust program to implement a function that multiplies all elements in an array.
Input:
Array: [2, 3, 4]
Expected Output:
Product: 24
Q42. Write a Rust program to demonstrate a match statement to handle multiple cases for a character input.
Input:
Character: 'a'
Expected Output:
It's a vowel
Q43. Write a Rust program to create a function that returns the number of elements greater than a given value in an array.
Input:
Array: [1, 3, 7, 10], Threshold: 5
Expected Output:
Count: 2
Q44. Write a Rust program to use nested for loops to print a multiplication table for numbers 1 through 5.
Input:
None
Expected Output:
1 2 3 4 5
2 4 6 8 10
3 6 9 12 15
4 8 12 16 20
5 10 15 20 25
Q45. Write a Rust program to demonstrate a simple function that swaps the values of two variables.
Input:
a = 3, b = 8
Expected Output:
Swapped: a = 8, b = 3
Q46. Write a Rust program to use a while loop to count the number of digits in a number.
Input:
Number: 12345
Expected Output:
Number of digits: 5
Q47. Write a Rust program to create a function that calculates the average of numbers in a vector.
Input:
Vector: [10, 20, 30]
Expected Output:
Average: 20.0
Q48. Write a Rust program to demonstrate the use of a loop to sum the first N natural numbers.
Input:
N = 5
Expected Output:
Sum: 15
Q49. Write a Rust program to use a match statement with a range to classify age groups.
Input:
Age: 25
Expected Output:
Category: Adult
Q50. Write a Rust program to create a function that finds the second largest number in an array.
Input:
Array: [10, 20, 15, 5]
Expected Output:
Second largest: 15
Q51. Write a Rust program to demonstrate an if-else condition to determine if a number is a prime number.
Input:
Number: 13
Expected Output:
Prime: true
Q52. Write a Rust program to create a function that removes duplicates from a vector.
Input:
Vector: [1, 2, 2, 3, 4, 4, 5]
Expected Output:
Unique vector: [1, 2, 3, 4, 5]
Q53. Write a Rust program to use nested if statements to determine the largest number among three inputs.
Input:
a = 3, b = 9, c = 5
Expected Output:
Largest number: 9
Q54. Write a Rust program to demonstrate the use of a function that returns multiple values using a tuple.
Input:
a = 10, b = 5
Expected Output:
Sum: 15, Product: 50
Q55. Write a Rust program to use a match statement with an enum to display a message based on traffic light colors.
Input:
Traffic light: Green
Expected Output:
Go
Q56. Write a Rust program to create a function that finds the first occurrence of a value in an array.
Input:
Array: [10, 20, 30, 40], Value: 30
Expected Output:
Index: 2
Q57. Write a Rust program to use a while loop to reverse the digits of a number.
Input:
Number: 1234
Expected Output:
Reversed: 4321
Q58. Write a Rust program to create a function that checks if a string contains a substring.
Input:
String: "Rust programming", Substring: "Rust"
Expected Output:
Contains substring: true
Q59. Write a Rust program to demonstrate the use of an early exit from a for loop using a break statement.
Input:
Stop at: 4
Expected Output:
Loop exited at 4
Q60. Write a Rust program to use a match statement to handle results returned by a function.
Input:
Value: Ok(5)
Expected Output:
Value is 5
Q61. Write a Rust program to create a function that checks if a number is a power of two.
Input:
Number: 16
Expected Output:
Is power of two: true
Q62. Write a Rust program to use a for loop to calculate the factorial of a number.
Input:
Number: 5
Expected Output:
Factorial: 120
Q63. Write a Rust program to demonstrate the use of a recursive function to calculate the Fibonacci sequence.
Input:
N = 6
Expected Output:
Fibonacci: 8
Q64. Write a Rust program to create a function that calculates the area of a rectangle.
Input:
Length = 10, Width = 5
Expected Output:
Area: 50
Q65. Write a Rust program to use a while loop to find the smallest divisor of a number greater than 1.
Input:
Number: 35
Expected Output:
Smallest divisor: 5
Q66. Write a Rust program to demonstrate a function that returns the maximum value in a slice.
Input:
Slice: [1, 4, 6, 8, 3]
Expected Output:
Maximum: 8
Q67. Write a Rust program to create a function that concatenates two strings.
Input:
String 1: "Hello", String 2: "World"
Expected Output:
Concatenated: "HelloWorld"
Q68. Write a Rust program to demonstrate the use of a for loop to print the indices and values of an array.
Input:
Array: [10, 20, 30]
Expected Output:
Index 0: 10
Index 1: 20
Index 2: 30
Q69. Write a Rust program to create a function that counts the number of words in a string.
Input:
String: "Rust is fun"
Expected Output:
Word count: 3
Q70. Write a Rust program to demonstrate a simple calculator using if-else statements.
Input:
Operation: '/', a = 20, b = 4
Expected Output:
Result: 5
Q71. Write a Rust program to create a function that calculates the nth power of a number using a loop.
Input:
Base = 2, Exponent = 4
Expected Output:
Result: 16
Q72. Write a Rust program to demonstrate a function that takes a slice and reverses its elements in-place.
Input:
Slice: [1, 2, 3, 4]
Expected Output:
Reversed slice: [4, 3, 2, 1]
Q73. Write a Rust program to use a for loop to print the ASCII values of characters in a string.
Input:
String: "ABC"
Expected Output:
65 66 67
Q74. Write a Rust program to create a function that checks if a vector is sorted in ascending order.
Input:
Vector: [1, 2, 3, 4, 5]
Expected Output:
Is sorted: true
Q75. Write a Rust program to demonstrate the use of a match statement to handle different error codes.
Input:
Error code: 404
Expected Output:
Not Found
Q76. Write a Rust program to use a while loop to compute the greatest common divisor (GCD) of two numbers.
Input:
a = 56, b = 98
Expected Output:
GCD: 14
Q77. Write a Rust program to create a function that checks if two strings are anagrams.
Input:
String 1: "listen", String 2: "silent"
Expected Output:
Are anagrams: true
Q78. Write a Rust program to demonstrate a function that calculates the sum of squares of elements in an array.
Input:
Array: [1, 2, 3]
Expected Output:
Sum of squares: 14
Q79. Write a Rust program to use a for loop to print the elements of a 2D array.
Input:
2D Array: [[1, 2], [3, 4]]
Expected Output:
1 2
3 4
Q80. Write a Rust program to create a function that calculates the median of a vector.
Input:
Vector: [5, 3, 8, 1, 9]
Expected Output:
Median: 5
Q81. Write a Rust program to use a recursive function to find the factorial of a number.
Input:
Number: 4
Expected Output:
Factorial: 24
Q82. Write a Rust program to create a function that converts a temperature from Celsius to Fahrenheit.
Input:
Celsius: 25
Expected Output:
Fahrenheit: 77.0
Q83. Write a Rust program to demonstrate the use of a for loop to iterate over the characters in a string.
Input:
String: "Rust"
Expected Output:
R
u
s
t
Q84. Write a Rust program to create a function that calculates the sum of all odd numbers in a vector.
Input:
Vector: [1, 2, 3, 4, 5]
Expected Output:
Sum of odd numbers: 9
Q85. Write a Rust program to use a while loop to calculate the sum of the digits of a number until the sum becomes a single digit.
Input:
Number: 987
Expected Output:
Final sum: 6
Q86. Write a Rust program to create a function that counts the frequency of each character in a string.
Input:
String: "hello"
Expected Output:
h: 1, e: 1, l: 2, o: 1
Q87. Write a Rust program to demonstrate a function that returns the last element of an array.
Input:
Array: [10, 20, 30, 40]
Expected Output:
Last element: 40
Q88. Write a Rust program to use a for loop to print all the multiples of 3 from 1 to 30.
Input:
None
Expected Output:
3 6 9 12 15 18 21 24 27 30
Q89. Write a Rust program to create a function that determines if a given string is a valid palindrome, ignoring spaces.
Input:
String: "nurses run"
Expected Output:
Is palindrome: true
Q90. Write a Rust program to demonstrate a function that takes two numbers and returns their greatest common divisor (GCD) and least common multiple (LCM).
Input:
a = 12, b = 15
Expected Output:
GCD: 3, LCM: 60
Q91. Write a Rust program to use a match statement to categorize a number as "small", "medium", or "large".
Input:
Number: 75
Expected Output:
Category: Large
Q92. Write a Rust program to create a function that calculates the product of all elements in a vector.
Input:
Vector: [1, 2, 3, 4]
Expected Output:
Product: 24
Q93. Write a Rust program to demonstrate a loop that continues until a random number between 1 and 10 equals 5.
Input:
Randomly generated
Expected Output:
Generated: 8
Generated: 2
Generated: 5
Stopped at 5
Q94. Write a Rust program to create a function that returns the number of uppercase and lowercase characters in a string.
Input:
String: "RustLang"
Expected Output:
Uppercase: 2, Lowercase: 6
Q95. Write a Rust program to demonstrate the use of an early exit from a recursive function using return.
Input:
Limit = 3
Expected Output:
Function stopped at recursion level 3
Q96. Write a Rust program to create a function that determines if a vector contains duplicates.
Input:
Vector: [1, 2, 3, 4, 1]
Expected Output:
Contains duplicates: true
Q97. Write a Rust program to use a for loop to print the reverse of a string.
Input:
String: "Rust"
Expected Output:
tsuR
Q98. Write a Rust program to create a function that calculates the harmonic mean of a vector of numbers.
Input:
Vector: [1, 2, 3]
Expected Output:
Harmonic mean: 1.636
Q99. Write a Rust program to demonstrate a while loop to repeatedly divide a number by 2 until it is less than 1.
Input:
Number: 16
Expected Output:
16
8
4
2
1
Q100. Write a Rust program to create a function that finds the longest word in a string.
Input:
String: "Rust is amazing"
Expected Output:
Longest word: amazing