41 lines
1.4 KiB
Java
41 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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*
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* <p>Heaps are tree-like data structures that allow storing elements in a specific way. Each node
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* corresponds to an element and has one parent node (except for the root) and at most two children
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* nodes. Every element contains a key, and those keys indicate how the tree shall be built. For
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* instance, for a min-heap, the key of a node shall be greater than or equal to its parent's and
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* lower than or equal to its children's (the opposite rule applies to a max-heap).
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*
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* <p>All heap-related operations (inserting or deleting an element, extracting the min or max) are
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* performed in O(log n) time.
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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 the highest
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* 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 right
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* 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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}
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