https://github.com/griba2001/urweb-pairing-heap

https://github.com/griba2001/urweb-pairing-heap

Last synced: 3 months ago
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• Host: GitHub
• URL: https://github.com/griba2001/urweb-pairing-heap
• Owner: griba2001
• Created: 2015-08-14T09:44:07.000Z (about 9 years ago)
• Default Branch: master
• Last Pushed: 2015-08-30T13:29:42.000Z (about 9 years ago)
• Last Synced: 2024-06-19T23:14:37.169Z (5 months ago)
• Size: 141 KB
• Stars: 0
• Watchers: 1
• Forks: 0
• Open Issues: 0
• Metadata Files:
  • Readme: README.md

Awesome Lists containing this project

• awesome-urweb - urweb-pairing-heap - A pairing heap implementation of a priority queue (Algorithms and Data Structures)

README

        
# urweb-pairing-heap

minHeap and maxHeap for items and also for pairs (priority, payload)

with functions: findTop, merge, insert, deleteTop, delete, decreaseKey,

empty, null, size, fromList, toList

```ocaml

(* invariants *)

val propHeap: t -> bool                             (* node subHeaps order *)

val propFromToList: eq item -> list item -> bool    (* content conservation *)

val propCheckAfterDeletes: eq item -> list item -> bool  (* content conservation after deleting half of original list *)

```

### Usage

```ocaml

(* max heap: priority to the major *)

structure MaxH = Heap.MkMaxHeap( struct 

                               type item = int

                               val ord_item = ord_int

                           end)

val test1 = 1 :: 2 :: 3 :: []

val maxPriorityList = MaxH.toList <| MaxH.fromList test1

(* min heap: priority to the minor *)

structure MinH = Heap.MkMinHeap( struct

                               type item = int

                               val ord_item = ord_int

                           end)

val test2 = 3 :: 2 :: 1 :: []

val minPriorityList = MinH.toList <| MinH.fromList test2

structure MinHP = HeapOfPairs.MkMinHeapOfPairs (struct

                                                  type prio = int

                                                  type payload = string

                                                  val ord_prio = ord_int

                                                end)

val test3 = (3, "c") :: (2, "b") :: (1, "a") :: []

val minPriorityListOfPairs = (MinHP.toList <<< MinHP.fromList) test3

structure MaxHP = HeapOfPairs.MkMaxHeapOfPairs (struct

                                                  type prio = int

                                                  type payload = string

                                                  val ord_prio = ord_int

                                                end)

val test4 = (1, "c") :: (2, "b") :: (3, "a") :: []

val maxPriorityListOfPairs = (MaxHP.toList <<< MaxHP.fromList) test4

```

### test task

tests lib/test/heap_UnitTest UrUnit assertions

```bash

urweb test1

./test1.exe -p 8082

browser http://localhost:8082

```

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