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How could I insert an array into an array of arrays?
In Perl 5 I would do it this way:
use Data::Dumper;
my @aoa = ( [ 'a', 'A' ], [ 'c', 'C' ] );
splice( @aoa, 1, 0, [ 'b', 'B' ] );
print Dumper \@aoa;
(In Perl 6 splice flattens the replacement)
850
To append one array to another, call the concat() method on the first array, passing it the second array as a parameter, e.g. const arr3 = arr1. concat(arr2) . The concat method will merge the two arrays and will return a new array.
Introduction to JavaScript multidimensional arrayJavaScript does not provide the multidimensional array natively. However, you can create a multidimensional array by defining an array of elements, where each element is also another array.
1 First get the element to be inserted, say x 2 Then get the position at which this element is to be inserted, say pos 3 Then shift the array elements from this position to one position forward, and do this for all the other elements next to... 4 Insert the element x now at the position pos, as this is now empty. More ...
To add an array to array at the beginning in JavaScript, use the array.unshift () method. The unshift () is a built-in JavaScript function that adds new elements to the beginning of an array and returns the new length. The elem1, elem2, …, elemX arguments are required. The element (s) to add to the beginning of the array.
If you want to insert another array into an array without creating a new one, the easiest way is to use either push or unshift with apply. Eg: a1 = [1,2,3,4,5]; a2 = [21,22]; // Insert a1 at beginning of a2 a2.unshift.apply (a2,a1); // Insert a1 at end of a2 a2.push.apply (a2,a1);
You can also add multiple elements by using multiple parameters in the push () method: The unshift () method inserts elements to the beginning of the array. The concat () method doesn’t actually append elements to an existing array but instead, creates a brand new array. This means that the original array won’t change. Why is this important?
my @aoa = ([1,2],[5,6]);
my @arr = 3,4;
splice(@aoa, 1, 0, [@arr,]); # or splice(@aoa, 1, 0, [[3, 4],]);
say @aoa.perl
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