PHP - Ds Map::count() Function

The PHP Ds\Map::count() function is used to retrieve the number of values in a map. The other programming languages such as Java and C++, the retrieved number of values is considered as the size of the map.

In other programming languages, the size() or length function (or property) returns the number of elements in the map. The Ds\Map::count() function does the same.

Syntax

Following is the syntax of the PHP Ds\Map::count() function −

public int Ds\Map::count(): int

Parameters

This function does not accept any parameter.

Return value

This function returns the number of elements present in the map.

Example 1

The following program demonstrates the usage of the PHP Ds\Map::count() function −

<?php  
   $map = new \Ds\Map([1, 2, 3, 4, 5]);
   echo "The map elements are: \n";
   foreach($map as $key=>$value){
	   echo "[".$key."] = ".$value."\n";
   }
   echo "The number of elements in map: ";
   #using the count() function
   print_r($map->count());
?>

Output

The above program generates the following output −

The map elements are:
[0] = 1
[1] = 2
[2] = 3
[3] = 4
[4] = 5
The number of elements in map: 5

Example 2

Following is another example of the PHP Ds\Map::count() function. We use this function to retrieve the number of elements of this map (['a', 'e']) −

<?php  
   $map = new \Ds\Map(['a', 'e']);
   echo "The map elements are: \n";
   print_r($map);
   echo "Number of values before adding new elements: ";
   print_r($map->count());
   #adding elements
   $map->put("i", 2);
   $map->put("o", 3);
   $map->put("u", 4);
   echo "\nAfter adding values: \n:";
   print_r($map);
   echo "Number of values after adding new elements: ";
   print_r($map->count());
?>

Output

The above program generates the following output −

The map elements are:
Ds\Map Object
(
    [0] => Ds\Pair Object
        (
            [key] => 0
            [value] => a
        )

    [1] => Ds\Pair Object
        (
            [key] => 1
            [value] => e
        )

)
Number of values before adding new elements: 2
After adding values:
:Ds\Map Object
(
    [0] => Ds\Pair Object
        (
            [key] => 0
            [value] => a
        )

    [1] => Ds\Pair Object
        (
            [key] => 1
            [value] => e
        )

    [2] => Ds\Pair Object
        (
            [key] => i
            [value] => 2
        )

    [3] => Ds\Pair Object
        (
            [key] => o
            [value] => 3
        )

    [4] => Ds\Pair Object
        (
            [key] => u
            [value] => 4
        )

)
Number of values after adding new elements: 5