PHP SplHeap next() Function

The SplHeap::next() function is an inbuilt function in PHP that is used to move to the next node. This will delete the top node of the heap. 

Generally, the Heap Data Structure is of two types.

• Max-Heap: In a Max-Heap the key present at the root node must be greatest among the keys present at all of its children. The same property must be recursively true for all sub-trees in that Binary Tree.
• Min-Heap: In a Min-Heap the key present at the root node must be minimum among the keys present at all of its children. The same property must be recursively true for all sub-trees in that Binary Tree.

Syntax:

void SplHeap::next()

Parameters: This function does not accept any parameter.

Return Value: This function does not return any value.

Below programs illustrate the SplHeap::next() function in PHP:

Example 1:

<?php 

// Create a new empty Min Heap 
$heap = new SplMinHeap(); 

// Insert elements into the heap
$heap->insert('System'.'<br/>'); 
$heap->insert('GFG'.'<br/>'); 
$heap->insert('ALGO'.'<br/>'); 
$heap->insert('C'.'<br/>');
$heap->insert('Geeks'.'<br/>'); 
$heap->insert('GeeksforGeeks'.'<br/>'); 

// Loop to display the current element of heap
for ($heap->top(); $heap->valid(); $heap->next()) {
    echo $heap->current() . "\n";
}

?>

Output:

ALGO
C
GFG
Geeks
GeeksforGeeks
System

Example 2:

<?php 

// Create a new empty Max Heap 
$heap = new SplMaxHeap(); 

// Insert elements into heap
$heap->insert('System'.'<br/>'); 
$heap->insert('GFG'.'<br/>'); 
$heap->insert('ALGO'.'<br/>'); 
$heap->insert('C'.'<br/>');
$heap->insert('Geeks'.'<br/>'); 
$heap->insert('GeeksforGeeks'.'<br/>'); 

// Loop to display the current element of heap
for ($heap->top(); $heap->valid(); $heap->next()) {
    echo $heap->current() . "\n";
}

?>

Output:

System
GeeksforGeeks
Geeks
GFG
C
ALGO

Reference: https://www.php.net/manual/en/splheap.next.php