40 lines
1.4 KiB
Java
40 lines
1.4 KiB
Java
package DataStructures.Heaps;
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/**
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* Interface common to heap data structures.<br>
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* <p>Heaps are tree-like data structures that allow storing elements in a specific
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* way. Each node corresponds to an element and has one parent node (except for the root) and
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* at most two children nodes. Every element contains a key, and those keys
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* indicate how the tree shall be built. For instance, for a min-heap, the key of a node shall
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* be greater than or equal to its parent's and lower than or equal to its children's (the opposite rule applies to a
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* max-heap).</p>
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* <p>All heap-related operations (inserting or deleting an element, extracting the min or max) are performed in
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* O(log n) time.</p>
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*
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* @author Nicolas Renard
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*/
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public interface Heap {
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/**
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* @return the top element in the heap, the one with lowest key for min-heap or with
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* the highest key for max-heap
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* @throws EmptyHeapException if heap is empty
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*/
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HeapElement getElement() throws EmptyHeapException;
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/**
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* Inserts an element in the heap. Adds it to then end and toggle it until it finds its
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* right position.
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*
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* @param element an instance of the HeapElement class.
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*/
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void insertElement(HeapElement element);
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/**
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* Delete an element in the heap.
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*
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* @param elementIndex int containing the position in the heap of the element to be deleted.
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*/
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void deleteElement(int elementIndex);
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} |