What is the Ds\Set reverse() function in PHP?
Overview
The Ds\Set::reverse() function is used to reverse the order of elements. The elements are reversed in place, which means it does not use any extra space to reverse the set.
Syntax
The Ds\Set::reverse() function can be declared as shown below:
void public Ds\Set::reverse ( void )
Note: The
Ds\Set::reverse()function does not have any input parameters.
Return value
The Ds\Set::reverse() function reverses the order of the elements of a set in place and does not have a return value.
Example
Consider the code snippet below, which demonstrates the use of the Ds\Set::reverse() function.
<?php$set1 = new \Ds\Set([0, 2, 4, 6, 8]);echo "set1 before reverse: ";var_dump($set1);$set1->reverse();echo "\nset1 after reverse: ";var_dump($set1);?>
Output
set1 before reverse: object(Ds\Set)#1 (5) {
[0]=>
int(0)
[1]=>
int(2)
[2]=>
int(4)
[3]=>
int(6)
[4]=>
int(8)
}
set1 after reverse: object(Ds\Set)#1 (5) {
[0]=>
int(8)
[1]=>
int(6)
[2]=>
int(4)
[3]=>
int(2)
[4]=>
int(0)
}
Explanation
We declare a set set1 in line 3. We use the Ds\Set::reverse() function in line 8 to reverse the order of the elements in set1.