PHP 7 Data Structures and Algorithms

Implementing sets using a PHP array

A set is a simply a collection of values without any particular order. It can contain any data type and we can run different set operations such as union, intersection, complement, and so on. As a set only contains values, we can construct a basic PHP array and assign values to it so that it grows dynamically. The following example shows two sets that we have defined; one contains some odd numbers and the other one has some prime numbers:

$odd = []; $odd[] = 1; $odd[] = 3; $odd[] = 5; $odd[] = 7; $odd[] = 9; $prime = []; $prime[] = 2; $prime[] = 3; $prime[] = 5; 

In order to check the existence of a value inside the set along with union, intersection, and complement operation, we can use the following example: ...