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Question 1. What is the primary use case of Perl? A) Game development B) Text processing, system administration, web development C) Mobile app development D) Machine learning Answer: B Explanation: Perl is widely used for text processing, system administration, and web development due to its powerful string handling and scripting capabilities. Question 2. Which philosophy is Perl known for? A) DRY B) KISS C) TIMTOWTDI D) SOLID Answer: C Explanation: TIMTOWTDI stands for "There Is More Than One Way To Do It," reflecting Perl's flexible approach to problem-solving. Question 3. What does the shebang line "#!/usr/bin/perl" indicate in a Perl script? A) The script should be compiled B) The location of the Perl interpreter C) The script is a batch file D) The script is written in Python Answer: B Explanation: The shebang line specifies the path to the Perl interpreter, allowing the script to be executed directly.
Question 4. What is the standard file extension for Perl scripts? A) .py B) .rb C) .pl D) .sh Answer: C Explanation: Perl scripts conventionally use the .pl extension. Question 5. Which pragma enforces variable declaration in Perl? A) use feature; B) use strict; C) use export; D) use base; Answer: B Explanation: 'use strict;' requires variables to be declared, helping to prevent bugs due to misspelled or undeclared variables. Question 6. What is the effect of 'use warnings;' in Perl code? A) Converts warnings into errors B) Disables all warnings C) Enables non-fatal warning messages D) Ignores errors Answer: C Explanation: 'use warnings;' displays non-fatal warning messages, helping catch potential problems during script execution.
Question 10. Which function removes the newline character from the end of a string? A) chop B) chomp C) trim D) cut Answer: B Explanation: 'chomp' removes the newline character, while 'chop' removes the last character regardless of what it is. Question 11. What is the result of the expression "3 x 4" in Perl? A) 12 B) "3333" C) "3" D) "3333" Answer: D Explanation: The 'x' operator repeats the string on its left by the number on its right, producing "3333". Question 12. Which operator concatenates two strings in Perl? A) + B). C) & D) || Answer: B Explanation: The dot (.) operator is used to join strings together. Question 13. How do you declare an array in Perl?
A) $array = (1,2,3); B) @array = (1,2,3); C) %array = (1,2,3); D) array = (1,2,3); Answer: B Explanation: Arrays are declared using the '@' sigil followed by the array name. Question 14. How do you access the third element in an array named @data? A) $data[3] B) @data[2] C) $data{2} D) $data[2] Answer: D Explanation: Array indices start at 0, so the third element is $data[2]. Question 15. Which function adds an element to the end of an array? A) shift B) unshift C) push D) pop Answer: C Explanation: 'push' appends elements to the end of an array. Question 16. What does the 'my' keyword do in Perl? A) Declares a global variable
C) check($var) D) isdef($var) Answer: A Explanation: The 'defined' function returns true if the variable has a value other than undef. Question 20. Which function sorts an array in ascending order? A) sort() B) reverse() C) grep() D) map() Answer: A Explanation: 'sort' returns a sorted list in ascending order. Question 21. What does the map function do in Perl? A) Filters elements from a list B) Applies a transformation to each element of a list C) Reverses a list D) Joins a list into a string Answer: B Explanation: 'map' executes a block of code for each element, returning a list of results. Question 22. What is @ARGV used for? A) Storing environment variables B) Command-line arguments C) Input from files
D) Error messages Answer: B Explanation: '@ARGV' contains the command-line arguments passed to the script. Question 23. How do you declare a hash in Perl? A) $hash = (key => value); B) @hash = (key => value); C) %hash = (key => value); D) hash = (key => value); Answer: C Explanation: Hashes are declared with the '%' sigil. Question 24. Which function lists all keys in a hash? A) values() B) keys() C) each() D) list() Answer: B Explanation: 'keys' returns a list of all the keys in a hash. Question 25. How do you check if a hash contains a specific key? A) exists $hash{'key'} B) defined $hash{'key'} C) found $hash{'key'} D) in $hash{'key'}
Explanation: '$!' stores the error message from the most recent system or file operation. Question 29. What is the purpose of 'use feature;' in Perl? A) To enable modern Perl features B) To disable warnings C) To enforce strict syntax D) To load modules Answer: A Explanation: 'use feature;' allows access to new or experimental features in Perl. Question 30. Which statement is used for single-line comments? A) // B) # C) /* D) ; Answer: B Explanation: Comments in Perl are preceded by the '#' character. Question 31. Which function outputs text to the console? A) echo B) print C) write D) out Answer: B Explanation: 'print' displays data to the standard output.
Question 32. Which function provides formatted output in Perl? A) printf B) format C) display D) show Answer: A Explanation: 'printf' outputs formatted text according to the specified format string. Question 33. What does 'chop' do in Perl? A) Removes the first character of a string B) Removes the last character of a string C) Removes all whitespace D) Removes the newline character Answer: B Explanation: 'chop' deletes the last character of a string, regardless of its value. Question 34. Which block structure is used in Perl for code grouping? A) () B) [] C) {} D) <> Answer: C Explanation: Curly braces '{}' are used to group code into blocks.
A) $array{1,2} B) @array[1,2] C) $array[1,2] D) %array[1,2] Answer: B Explanation: Array slices are accessed using '@array[indices]'. Question 39. How do you remove and return the last element of an array? A) shift B) unshift C) pop D) delete Answer: C Explanation: 'pop' removes and returns the last array element. Question 40. What does the 'splice' function do? A) Adds elements to the beginning B) Removes and replaces elements in an array C) Sorts the array D) Joins elements Answer: B Explanation: 'splice' can remove, replace, or insert elements within an array. Question 41. Which function reverses the elements of an array? A) sort
B) reverse C) swap D) flip Answer: B Explanation: 'reverse' returns the array with its elements in reverse order. Question 42. What does 'grep' do in Perl? A) Finds the largest element B) Filters elements matching a condition C) Sorts the array D) Maps values Answer: B Explanation: 'grep' returns a list of elements that match a condition. Question 43. Which operator is used to create key/value pairs in hashes? A) => B) == C) = D) : Answer: A Explanation: The '=>' fat comma operator is used for clarity in hash initialization. Question 44. Which function returns all values of a hash? A) keys B) values
D) Loop control Answer: B Explanation: Setting '$|' to a true value forces a flush after each write or print. Question 48. Which control structure executes code if a condition is true? A) while B) if C) for D) foreach Answer: B Explanation: 'if' executes a block of code when its condition evaluates to true. Question 49. How do you write an 'else if' statement in Perl? A) elseif B) elsif C) else if D) else_if Answer: B Explanation: Perl uses 'elsif' for additional conditional branches. Question 50. What does 'unless' do in Perl? A) Executes code when a condition is true B) Executes code when a condition is false C) Skips code D) Repeats code
Answer: B Explanation: 'unless' executes its block if the condition is false. Question 51. Which statement modifier executes code conditionally? A) print $x if $y > 0; B) print $x unless $y > 0; C) print $x while $y > 0; D) print $x foreach @y; Answer: A Explanation: Statement modifiers allow concise conditional execution at the end of a statement. Question 52. Which structure provides switch-case-like behavior? A) select B) case C) given/when D) match Answer: C Explanation: The 'given/when' structure in Perl offers switch-case logic. Question 53. Which loop executes as long as a condition is true? A) for B) foreach C) while D) do-while Answer: C
Question 57. Which keyword restarts the current iteration of a loop? A) redo B) next C) restart D) continue Answer: A Explanation: 'redo' restarts the iteration without evaluating the loop condition again. Question 58. How do you label loops for nested control in Perl? A) label: for (...) B) for label (...) C) labeled for (...) D) :label for (...) Answer: A Explanation: Loops can be labeled with a colon for use with 'next', 'last', or 'redo'. Question 59. How do you define a subroutine in Perl? A) function foo {} B) sub foo {} C) def foo {} D) proc foo {} Answer: B Explanation: Subroutines are defined using the 'sub' keyword.
Question 60. How do you access arguments passed to a subroutine? A) $args B) @_ C) $ARGV D) $params Answer: B Explanation: '@_' is the default array containing subroutine arguments. Question 61. What does the 'return' keyword do in a subroutine? A) Ends the program B) Returns a value from the subroutine C) Prints output D) Declares a variable Answer: B Explanation: 'return' passes a value back to the caller. Question 62. What is the difference between 'my' and 'local' for variable scope? A) Both give global scope B) 'my' gives lexical scope; 'local' gives dynamic scope C) Both give lexical scope D) Both give dynamic scope Answer: B Explanation: 'my' creates variables with lexical (block) scope, while 'local' temporarily changes the value for the current dynamic scope. Question 63. What is a reference in Perl?
