Perl | unshift() Function Last Updated : 06 Mar, 2023 Comments Improve Suggest changes Like Article Like Report unshift() function in Perl places the given list of elements at the beginning of an array. Thereby shifting all the values in the array by right. Multiple values can be unshift using this operation. This function returns the number of new elements in an array. Syntax: unshift(Array, List)Returns: Number of new elements in Array Example 1: Perl #!/usr/bin/perl # Initializing the array @x = ('Geeks', 'for', 'Geeks'); # Print the Initial array print "Original array: @x \n"; # Prints the number of elements # returned by unshift print "No of elements returned by unshift: ", unshift(@x, 'Welcome', 'to'); # Array after unshift operation print "\nUpdated array: @x"; Output: Original array: Geeks for Geeks No of elements returned by unshift: 5 Updated array: Welcome to Geeks for Geeks Example 2: Perl #!/usr/bin/perl # Initializing the array @x = (10, 20, 30, 40, 50); # Print the Initial array print "Original array: @x \n"; # Prints the number of elements # returned by unshift print "No of elements returned by unshift: ", unshift(@x, 70, 80, 'Geeks'); # Array after unshift operation print "\nUpdated array: @x"; Output: Original array: 10 20 30 40 50 No of elements returned by unshift: 8 Updated array: 70 80 Geeks 10 20 30 40 50 Example - 3 : Unshifting two lists. Perl #!/usr/bin/perl my @arr_1 = ("is","the","best"); my @arr_2 = ("Geeks","for","Geeks"); unshift @arr_1, @arr_2; print("@arr_1"); Output - Comment More infoAdvertise with us Next Article Perl | unshift() Function C Code_Mech Follow Improve Article Tags : Perl Perl-function Perl-Array-Functions Similar Reads Perl | shift() Function shift() function in Perl returns the first value in an array, removing it and shifting the elements of the array list to the left by one. Shift operation removes the value like pop but is taken from the start of the array instead of the end as in pop. This function returns undef if the array is empt 2 min read Perl | sqrt() Function Many times it happens that while solving mathematical expressions we require to calculate the square root of a number. To solve this issue, like other programming language Perl provides us with a built-in function sqrt() which can be used to calculate the square root of a number. 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