The SplHeap::isEmpty() function is an inbuilt function in PHP which is used to check whether the heap is empty or not.
Generally, the Heap Data Structure are 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:
bool SplHeap::isEmpty()
Parameters: This function does not accept any parameter.
Return Value: This function returns whether the heap is empty.Â
Below programs illustrate the SplHeap::isEmpty() function in PHP:
Example 1:
PHP
<?php   // Create a new empty Max Heap $heap1 = new SplMaxHeap();   // Create a new empty Max Heap $heap2 = new SplMaxHeap();   // Insert elements in max heap $heap2->insert('System'); $heap2->insert('GFG');   // Check heap is empty or not var_dump($heap1->isEmpty());   var_dump($heap2->isEmpty());   ?> |
Output:
bool(true) bool(false)
Example 2:
PHP
<?php   // Create a new empty Min Heap $heap1 = new SplMinHeap();   // Create a new empty Max Heap $heap2 = new SplMinHeap();   // Insert elements in min heap $heap2->insert('System'); $heap2->insert('GFG');   // Check heap is empty or not var_dump($heap1->isEmpty());   var_dump($heap2->isEmpty());   ?> |
Output:
bool(true) bool(false)
Reference: https://www.php.net/manual/en/splheap.isempty.php
