Tumpukan Fibonacci

Dalam tutorial ini, anda akan mengetahui apa itu Fibonacci Heap. Anda juga akan mendapat contoh operasi yang berbeza pada timbunan fibonacci di C, C ++, Java dan Python.

Tumpukan Fibonacci adalah bentuk timbunan binomial yang diubahsuai dengan operasi timbunan yang lebih cekap daripada yang disokong oleh timbunan binomial dan binari.

Tidak seperti timbunan binari, nod boleh mempunyai lebih daripada dua anak.

The fibonacci timbunan dipanggil fibonacci timbunan kerana pokok-pokok yang dibina dalam apa-apa cara yang pokok perintah n mempunyai sekurang-kurangnya Fn+2nod di dalamnya, di mana Fn+2adalah (n + 2)ndnombor Fibonacci.

Tumpukan Fibonacci

Sifat timbunan Fibonacci

Sifat penting timbunan Fibonacci adalah:

  1. Ini adalah sekumpulan pokok yang dipesan minimum . (iaitu ibu bapa selalu lebih kecil daripada anak-anak.)
  2. Penunjuk dikekalkan pada simpul elemen minimum.
  3. Ia terdiri daripada satu set nod yang ditandakan. (Kurangkan operasi kunci)
  4. Pokok di dalam timbunan Fibonacci tidak tersusun tetapi berakar.

Perwakilan Ingatan bagi Node dalam Tumpukan Fibonacci

Akar semua pokok dihubungkan untuk akses yang lebih pantas. Nod anak dari nod induk dihubungkan antara satu sama lain melalui senarai berganda berpaut bulat seperti ditunjukkan di bawah.

Terdapat dua kelebihan utama menggunakan senarai berpaut berganda berpaut.

  1. Memadamkan nod dari pokok memerlukan O(1)masa.
  2. Gabungan dua senarai tersebut memerlukan O(1)masa.
Struktur timbunan Fibonacci

Operasi di Fibonacci Heap

Penyisipan

Algoritma

 masukkan (H, x) darjah (x) = 0 p (x) = Anak NIL (x) = NIL kiri (x) = x kanan (x) = x tanda (x) = SALAT menggabungkan senarai akar yang mengandungi x dengan akar senaraikan H jika min (H) == NIL atau kekunci (x) <kekunci (min (H)) maka min (H) = xn (H) = n (H) + 1 

Memasukkan nod ke timbunan yang sudah ada mengikuti langkah-langkah di bawah.

  1. Buat simpul baru untuk elemen.
  2. Periksa sama ada timbunan itu kosong.
  3. Sekiranya timbunan kosong, tetapkan simpul baru sebagai simpul akar dan tandakan min.
  4. Jika tidak, masukkan node ke dalam senarai root dan kemas kini min.
Contoh Penyisipan

Cari Min

Elemen minimum selalu diberikan oleh penunjuk min.

Kesatuan

Kesatuan dua timbunan fibonacci terdiri daripada langkah-langkah berikut.

  1. Gabungkan akar kedua timbunan.
  2. Kemas kini min dengan memilih kunci minimum dari senarai root baru.
Kesatuan dua timbunan

Ekstrak Min

Ini adalah operasi yang paling penting pada timbunan fibonacci. Dalam operasi ini, simpul dengan nilai minimum dikeluarkan dari timbunan dan pokok diselaraskan semula.

Langkah-langkah berikut diikuti:

  1. Padamkan nod min.
  2. Tetapkan pointer min ke root seterusnya dalam senarai root.
  3. Buat susunan ukuran yang sama dengan tahap maksimum pokok di timbunan sebelum penghapusan.
  4. Lakukan perkara berikut (langkah 5-7) sehingga tidak ada pelbagai akar dengan tahap yang sama.
  5. Petakan tahap punca semasa (min-pointer) ke tahap dalam array.
  6. Petakan tahap punca seterusnya ke darjah dalam array.
  7. Sekiranya terdapat lebih dari dua pemetaan untuk tahap yang sama, maka lakukan operasi penyatuan pada akar tersebut sehingga harta min-heap dikekalkan (iaitu minimum berada pada akar).

Pelaksanaan langkah-langkah di atas dapat difahami dalam contoh di bawah.

  1. Kami akan melakukan operasi ekstrak-min di timbunan di bawah. Tumpukan Fibonacci
  2. Padamkan simpul min, tambahkan semua nod anak ke senarai akar dan tetapkan penunjuk min ke akar seterusnya dalam senarai akar. Padamkan nod min
  3. Darjah maksimum di pohon ialah 3. Buat susunan ukuran 4 dan darjah peta akar seterusnya dengan tatasusunan. Buat tatasusunan
  4. Di sini, 23 dan 7 mempunyai darjah yang sama, jadi satukan mereka. Satukan mereka yang mempunyai darjah yang sama
  5. Sekali lagi, 7 dan 17 mempunyai darjah yang sama, jadi satukan mereka juga. Satukan mereka yang mempunyai darjah yang sama
  6. Sekali lagi 7 dan 24 mempunyai darjah yang sama, jadi satukan mereka. Satukan mereka yang mempunyai darjah yang sama
  7. Petakan nod seterusnya. Petakan nod yang tinggal
  8. Sekali lagi, 52 dan 21 mempunyai darjah yang sama, jadi satukan mereka Bersatu yang mempunyai darjah yang sama
  9. Begitu juga, satukan 21 dan 18. Bersatu mereka yang mempunyai darjah yang sama
  10. Petakan akar yang tinggal. Petakan nod yang tinggal
  11. Tumpukan terakhir adalah. Timbunan fibonacci akhir

Menurunkan Kekunci dan Menghapus Node

Ini adalah operasi terpenting yang dibincangkan dalam Operasi Turunkan Kekunci dan Hapus Node.

Contoh Python, Java dan C / C ++

Python Java C C +
 # Fibonacci Heap in python import math # Creating fibonacci tree class FibonacciTree: def __init__(self, value): self.value = value self.child = () self.order = 0 # Adding tree at the end of the tree def add_at_end(self, t): self.child.append(t) self.order = self.order + 1 # Creating Fibonacci heap class FibonacciHeap: def __init__(self): self.trees = () self.least = None self.count = 0 # Insert a node def insert_node(self, value): new_tree = FibonacciTree(value) self.trees.append(new_tree) if (self.least is None or value y.value: x, y = y, x x.add_at_end(y) aux(order) = None order = order + 1 aux(order) = x self.least = None for k in aux: if k is not None: self.trees.append(k) if (self.least is None or k.value < self.least.value): self.least = k def floor_log(x): return math.frexp(x)(1) - 1 fibonacci_heap = FibonacciHeap() fibonacci_heap.insert_node(7) fibonacci_heap.insert_node(3) fibonacci_heap.insert_node(17) fibonacci_heap.insert_node(24) print('the minimum value of the fibonacci heap: ()'.format(fibonacci_heap.get_min())) print('the minimum value removed: ()'.format(fibonacci_heap.extract_min())) 
 // Operations on Fibonacci Heap in Java // Node creation class node ( node parent; node left; node right; node child; int degree; boolean mark; int key; public node() ( this.degree = 0; this.mark = false; this.parent = null; this.left = this; this.right = this; this.child = null; this.key = Integer.MAX_VALUE; ) node(int x) ( this(); this.key = x; ) void set_parent(node x) ( this.parent = x; ) node get_parent() ( return this.parent; ) void set_left(node x) ( this.left = x; ) node get_left() ( return this.left; ) void set_right(node x) ( this.right = x; ) node get_right() ( return this.right; ) void set_child(node x) ( this.child = x; ) node get_child() ( return this.child; ) void set_degree(int x) ( this.degree = x; ) int get_degree() ( return this.degree; ) void set_mark(boolean m) ( this.mark = m; ) boolean get_mark() ( return this.mark; ) void set_key(int x) ( this.key = x; ) int get_key() ( return this.key; ) ) public class fibHeap ( node min; int n; boolean trace; node found; public boolean get_trace() ( return trace; ) public void set_trace(boolean t) ( this.trace = t; ) public static fibHeap create_heap() ( return new fibHeap(); ) fibHeap() ( min = null; n = 0; trace = false; ) private void insert(node x) ( if (min == null) ( min = x; x.set_left(min); x.set_right(min); ) else ( x.set_right(min); x.set_left(min.get_left()); min.get_left().set_right(x); min.set_left(x); if (x.get_key() "); temp = temp.get_right(); ) while (temp != c); System.out.print(")"); ) ) public static void merge_heap(fibHeap H1, fibHeap H2, fibHeap H3) ( H3.min = H1.min; if (H1.min != null && H2.min != null) ( node t1 = H1.min.get_left(); node t2 = H2.min.get_left(); H1.min.set_left(t2); t1.set_right(H2.min); H2.min.set_left(t1); t2.set_right(H1.min); ) if (H1.min == null || (H2.min != null && H2.min.get_key() < H1.min.get_key())) H3.min = H2.min; H3.n = H1.n + H2.n; ) public int find_min() ( return this.min.get_key(); ) private void display_node(node z) ( System.out.println("right: " + ((z.get_right() == null) ? "-1" : z.get_right().get_key())); System.out.println("left: " + ((z.get_left() == null) ? "-1" : z.get_left().get_key())); System.out.println("child: " + ((z.get_child() == null) ? "-1" : z.get_child().get_key())); System.out.println("degree " + z.get_degree()); ) public int extract_min() ( node z = this.min; if (z != null) ( node c = z.get_child(); node k = c, p; if (c != null) ( do ( p = c.get_right(); insert(c); c.set_parent(null); c = p; ) while (c != null && c != k); ) z.get_left().set_right(z.get_right()); z.get_right().set_left(z.get_left()); z.set_child(null); if (z == z.get_right()) this.min = null; else ( this.min = z.get_right(); this.consolidate(); ) this.n -= 1; return z.get_key(); ) return Integer.MAX_VALUE; ) public void consolidate() ( double phi = (1 + Math.sqrt(5)) / 2; int Dofn = (int) (Math.log(this.n) / Math.log(phi)); node() A = new node(Dofn + 1); for (int i = 0; i y.get_key()) ( node temp = x; x = y; y = temp; w = x; ) fib_heap_link(y, x); check = x; A(d) = null; d += 1; ) A(d) = x; w = w.get_right(); ) while (w != null && w != check); this.min = null; for (int i = 0; i <= Dofn; ++i) ( if (A(i) != null) ( insert(A(i)); ) ) ) ) // Linking operation private void fib_heap_link(node y, node x) ( y.get_left().set_right(y.get_right()); y.get_right().set_left(y.get_left()); node p = x.get_child(); if (p == null) ( y.set_right(y); y.set_left(y); ) else ( y.set_right(p); y.set_left(p.get_left()); p.get_left().set_right(y); p.set_left(y); ) y.set_parent(x); x.set_child(y); x.set_degree(x.get_degree() + 1); y.set_mark(false); ) // Search operation private void find(int key, node c) ( if (found != null || c == null) return; else ( node temp = c; do ( if (key == temp.get_key()) found = temp; else ( node k = temp.get_child(); find(key, k); temp = temp.get_right(); ) ) while (temp != c && found == null); ) ) public node find(int k) ( found = null; find(k, this.min); return found; ) public void decrease_key(int key, int nval) ( node x = find(key); decrease_key(x, nval); ) // Decrease key operation private void decrease_key(node x, int k) ( if (k> x.get_key()) return; x.set_key(k); node y = x.get_parent(); if (y != null && x.get_key() < y.get_key()) ( cut(x, y); cascading_cut(y); ) if (x.get_key() < min.get_key()) min = x; ) // Cut operation private void cut(node x, node y) ( x.get_right().set_left(x.get_left()); x.get_left().set_right(x.get_right()); y.set_degree(y.get_degree() - 1); x.set_right(null); x.set_left(null); insert(x); x.set_parent(null); x.set_mark(false); ) private void cascading_cut(node y) ( node z = y.get_parent(); if (z != null) ( if (y.get_mark() == false) y.set_mark(true); else ( cut(y, z); cascading_cut(z); ) ) ) // Delete operations public void delete(node x) ( decrease_key(x, Integer.MIN_VALUE); int p = extract_min(); ) public static void main(String() args) ( fibHeap obj = create_heap(); obj.insert(7); obj.insert(26); obj.insert(30); obj.insert(39); obj.insert(10); obj.display(); System.out.println(obj.extract_min()); obj.display(); System.out.println(obj.extract_min()); obj.display(); System.out.println(obj.extract_min()); obj.display(); System.out.println(obj.extract_min()); obj.display(); System.out.println(obj.extract_min()); obj.display(); ) )
 // Operations on a Fibonacci heap in C #include #include #include #include typedef struct _NODE ( int key; int degree; struct _NODE *left_sibling; struct _NODE *right_sibling; struct _NODE *parent; struct _NODE *child; bool mark; bool visited; ) NODE; typedef struct fibanocci_heap ( int n; NODE *min; int phi; int degree; ) FIB_HEAP; FIB_HEAP *make_fib_heap(); void insertion(FIB_HEAP *H, NODE *new, int val); NODE *extract_min(FIB_HEAP *H); void consolidate(FIB_HEAP *H); void fib_heap_link(FIB_HEAP *H, NODE *y, NODE *x); NODE *find_min_node(FIB_HEAP *H); void decrease_key(FIB_HEAP *H, NODE *node, int key); void cut(FIB_HEAP *H, NODE *node_to_be_decrease, NODE *parent_node); void cascading_cut(FIB_HEAP *H, NODE *parent_node); void Delete_Node(FIB_HEAP *H, int dec_key); FIB_HEAP *make_fib_heap() ( FIB_HEAP *H; H = (FIB_HEAP *)malloc(sizeof(FIB_HEAP)); H->n = 0; H->min = NULL; H->phi = 0; H->degree = 0; return H; ) // Printing the heap void print_heap(NODE *n) ( NODE *x; for (x = n;; x = x->right_sibling) ( if (x->child == NULL) ( printf("node with no child (%d) ", x->key); ) else ( printf("NODE(%d) with child (%d)", x->key, x->child->key); print_heap(x->child); ) if (x->right_sibling == n) ( break; ) ) ) // Inserting nodes void insertion(FIB_HEAP *H, NODE *new, int val) ( new = (NODE *)malloc(sizeof(NODE)); new->key = val; new->degree = 0; new->mark = false; new->parent = NULL; new->child = NULL; new->visited = false; new->left_sibling = new; new->right_sibling = new; if (H->min == NULL) ( H->min = new; ) else ( H->min->left_sibling->right_sibling = new; new->right_sibling = H->min; new->left_sibling = H->min->left_sibling; H->min->left_sibling = new; if (new->key min->key) ( H->min = new; ) ) (H->n)++; ) // Find min node NODE *find_min_node(FIB_HEAP *H) ( if (H == NULL) ( printf(" Fibonacci heap not yet created "); return NULL; ) else return H->min; ) // Union operation FIB_HEAP *unionHeap(FIB_HEAP *H1, FIB_HEAP *H2) ( FIB_HEAP *Hnew; Hnew = make_fib_heap(); Hnew->min = H1->min; NODE *temp1, *temp2; temp1 = Hnew->min->right_sibling; temp2 = H2->min->left_sibling; Hnew->min->right_sibling->left_sibling = H2->min->left_sibling; Hnew->min->right_sibling = H2->min; H2->min->left_sibling = Hnew->min; temp2->right_sibling = temp1; if ((H1->min == NULL) || (H2->min != NULL && H2->min->key min->key)) Hnew->min = H2->min; Hnew->n = H1->n + H2->n; return Hnew; ) // Calculate the degree int cal_degree(int n) ( int count = 0; while (n> 0) ( n = n / 2; count++; ) return count; ) // Consolidate function void consolidate(FIB_HEAP *H) ( int degree, i, d; degree = cal_degree(H->n); NODE *A(degree), *x, *y, *z; for (i = 0; i min; do ( d = x->degree; while (A(d) != NULL) ( y = A(d); if (x->key> y->key) ( NODE *exchange_help; exchange_help = x; x = y; y = exchange_help; ) if (y == H->min) H->min = x; fib_heap_link(H, y, x); if (y->right_sibling == x) H->min = x; A(d) = NULL; d++; ) A(d) = x; x = x->right_sibling; ) while (x != H->min); H->min = NULL; for (i = 0; i left_sibling = A(i); A(i)->right_sibling = A(i); if (H->min == NULL) ( H->min = A(i); ) else ( H->min->left_sibling->right_sibling = A(i); A(i)->right_sibling = H->min; A(i)->left_sibling = H->min->left_sibling; H->min->left_sibling = A(i); if (A(i)->key min->key) ( H->min = A(i); ) ) if (H->min == NULL) ( H->min = A(i); ) else if (A(i)->key min->key) ( H->min = A(i); ) ) ) ) // Linking void fib_heap_link(FIB_HEAP *H, NODE *y, NODE *x) ( y->right_sibling->left_sibling = y->left_sibling; y->left_sibling->right_sibling = y->right_sibling; if (x->right_sibling == x) H->min = x; y->left_sibling = y; y->right_sibling = y; y->parent = x; if (x->child == NULL) ( x->child = y; ) y->right_sibling = x->child; y->left_sibling = x->child->left_sibling; x->child->left_sibling->right_sibling = y; x->child->left_sibling = y; if ((y->key) child->key)) x->child = y; (x->degree)++; ) // Extract min NODE *extract_min(FIB_HEAP *H) ( if (H->min == NULL) printf(" The heap is empty"); else ( NODE *temp = H->min; NODE *pntr; pntr = temp; NODE *x = NULL; if (temp->child != NULL) ( x = temp->child; do ( pntr = x->right_sibling; (H->min->left_sibling)->right_sibling = x; x->right_sibling = H->min; x->left_sibling = H->min->left_sibling; H->min->left_sibling = x; if (x->key min->key) H->min = x; x->parent = NULL; x = pntr; ) while (pntr != temp->child); ) (temp->left_sibling)->right_sibling = temp->right_sibling; (temp->right_sibling)->left_sibling = temp->left_sibling; H->min = temp->right_sibling; if (temp == temp->right_sibling && temp->child == NULL) H->min = NULL; else ( H->min = temp->right_sibling; consolidate(H); ) H->n = H->n - 1; return temp; ) return H->min; ) void cut(FIB_HEAP *H, NODE *node_to_be_decrease, NODE *parent_node) ( NODE *temp_parent_check; if (node_to_be_decrease == node_to_be_decrease->right_sibling) parent_node->child = NULL; node_to_be_decrease->left_sibling->right_sibling = node_to_be_decrease->right_sibling; node_to_be_decrease->right_sibling->left_sibling = node_to_be_decrease->left_sibling; if (node_to_be_decrease == parent_node->child) parent_node->child = node_to_be_decrease->right_sibling; (parent_node->degree)--; node_to_be_decrease->left_sibling = node_to_be_decrease; node_to_be_decrease->right_sibling = node_to_be_decrease; H->min->left_sibling->right_sibling = node_to_be_decrease; node_to_be_decrease->right_sibling = H->min; node_to_be_decrease->left_sibling = H->min->left_sibling; H->min->left_sibling = node_to_be_decrease; node_to_be_decrease->parent = NULL; node_to_be_decrease->mark = false; ) void cascading_cut(FIB_HEAP *H, NODE *parent_node) ( NODE *aux; aux = parent_node->parent; if (aux != NULL) ( if (parent_node->mark == false) ( parent_node->mark = true; ) else ( cut(H, parent_node, aux); cascading_cut(H, aux); ) ) ) void decrease_key(FIB_HEAP *H, NODE *node_to_be_decrease, int new_key) ( NODE *parent_node; if (H == NULL) ( printf(" FIbonacci heap not created "); return; ) if (node_to_be_decrease == NULL) ( printf("Node is not in the heap"); ) else ( if (node_to_be_decrease->key key = new_key; parent_node = node_to_be_decrease->parent; if ((parent_node != NULL) && (node_to_be_decrease->key key)) ( printf(" cut called"); cut(H, node_to_be_decrease, parent_node); printf(" cascading cut called"); cascading_cut(H, parent_node); ) if (node_to_be_decrease->key min->key) ( H->min = node_to_be_decrease; ) ) ) ) void *find_node(FIB_HEAP *H, NODE *n, int key, int new_key) ( NODE *find_use = n; NODE *f = NULL; find_use->visited = true; if (find_use->key == key) ( find_use->visited = false; f = find_use; decrease_key(H, f, new_key); ) if (find_use->child != NULL) ( find_node(H, find_use->child, key, new_key); ) if ((find_use->right_sibling->visited != true)) ( find_node(H, find_use->right_sibling, key, new_key); ) find_use->visited = false; ) FIB_HEAP *insertion_procedure() ( FIB_HEAP *temp; int no_of_nodes, ele, i; NODE *new_node; temp = (FIB_HEAP *)malloc(sizeof(FIB_HEAP)); temp = NULL; if (temp == NULL) ( temp = make_fib_heap(); ) printf(" enter number of nodes to be insert = "); scanf("%d", &no_of_nodes); for (i = 1; i min, dec_key, -5000); p = extract_min(H); if (p != NULL) printf(" Node deleted"); else printf(" Node not deleted:some error"); ) int main(int argc, char **argv) ( NODE *new_node, *min_node, *extracted_min, *node_to_be_decrease, *find_use; FIB_HEAP *heap, *h1, *h2; int operation_no, new_key, dec_key, ele, i, no_of_nodes; heap = (FIB_HEAP *)malloc(sizeof(FIB_HEAP)); heap = NULL; while (1) ( printf(" Operations 1. Create Fibonacci heap 2. Insert nodes into fibonacci heap 3. Find min 4. Union 5. Extract min 6. Decrease key 7.Delete node 8. print heap 9. exit enter operation_no = "); scanf("%d", &operation_no); switch (operation_no) ( case 1: heap = make_fib_heap(); break; case 2: if (heap == NULL) ( heap = make_fib_heap(); ) printf(" enter number of nodes to be insert = "); scanf("%d", &no_of_nodes); for (i = 1; i key); break; case 4: if (heap == NULL) ( printf(" no FIbonacci heap created "); break; ) h1 = insertion_procedure(); heap = unionHeap(heap, h1); printf("Unified Heap:"); print_heap(heap->min); break; case 5: if (heap == NULL) printf("Empty Fibonacci heap"); else ( extracted_min = extract_min(heap); printf(" min value = %d", extracted_min->key); printf(" Updated heap: "); print_heap(heap->min); ) break; case 6: if (heap == NULL) printf("Fibonacci heap is empty"); else ( printf(" node to be decreased = "); scanf("%d", &dec_key); printf(" enter the new key = "); scanf("%d", &new_key); find_use = heap->min; find_node(heap, find_use, dec_key, new_key); printf(" Key decreased- Corresponding heap:"); print_heap(heap->min); ) break; case 7: if (heap == NULL) printf("Fibonacci heap is empty"); else ( printf(" Enter node key to be deleted = "); scanf("%d", &dec_key); Delete_Node(heap, dec_key); printf(" Node Deleted- Corresponding heap:"); print_heap(heap->min); break; ) case 8: print_heap(heap->min); break; case 9: free(new_node); free(heap); exit(0); default: printf("Invalid choice "); ) ) )
 // Operations on a Fibonacci heap in C++ #include #include #include using namespace std; // Node creation struct node ( int n; int degree; node *parent; node *child; node *left; node *right; char mark; char C; ); // Implementation of Fibonacci heap class FibonacciHeap ( private: int nH; node *H; public: node *InitializeHeap(); int Fibonnaci_link(node *, node *, node *); node *Create_node(int); node *Insert(node *, node *); node *Union(node *, node *); node *Extract_Min(node *); int Consolidate(node *); int Display(node *); node *Find(node *, int); int Decrease_key(node *, int, int); int Delete_key(node *, int); int Cut(node *, node *, node *); int Cascase_cut(node *, node *); FibonacciHeap() ( H = InitializeHeap(); ) ); // Initialize heap node *FibonacciHeap::InitializeHeap() ( node *np; np = NULL; return np; ) // Create node node *FibonacciHeap::Create_node(int value) ( node *x = new node; x->n = value; return x; ) // Insert node node *FibonacciHeap::Insert(node *H, node *x) ( x->degree = 0; x->parent = NULL; x->child = NULL; x->left = x; x->right = x; x->mark = 'F'; x->C = 'N'; if (H != NULL) ( (H->left)->right = x; x->right = H; x->left = H->left; H->left = x; if (x->n n) H = x; ) else ( H = x; ) nH = nH + 1; return H; ) // Create linking int FibonacciHeap::Fibonnaci_link(node *H1, node *y, node *z) ( (y->left)->right = y->right; (y->right)->left = y->left; if (z->right == z) H1 = z; y->left = y; y->right = y; y->parent = z; if (z->child == NULL) z->child = y; y->right = z->child; y->left = (z->child)->left; ((z->child)->left)->right = y; (z->child)->left = y; if (y->n child)->n) z->child = y; z->degree++; ) // Union Operation node *FibonacciHeap::Union(node *H1, node *H2) ( node *np; node *H = InitializeHeap(); H = H1; (H->left)->right = H2; (H2->left)->right = H; np = H->left; H->left = H2->left; H2->left = np; return H; ) // Display the heap int FibonacciHeap::Display(node *H) ( node *p = H; if (p == NULL) ( cout << "Empty Heap" << endl; return 0; ) cout << "Root Nodes: " << endl; do ( cout  right; if (p != H) ( cout <"; ) ) while (p != H && p->right != NULL); cout <  child != NULL) x = z->child; if (x != NULL) ( ptr = x; do ( np = x->right; (H1->left)->right = x; x->right = H1; x->left = H1->left; H1->left = x; if (x->n n) H1 = x; x->parent = NULL; x = np; ) while (np != ptr); ) (z->left)->right = z->right; (z->right)->left = z->left; H1 = z->right; if (z == z->right && z->child == NULL) H = NULL; else ( H1 = z->right; Consolidate(H1); ) nH = nH - 1; return p; ) // Consolidation Function int FibonacciHeap::Consolidate(node *H1) ( int d, i; float f = (log(nH)) / (log(2)); int D = f; node *A(D); for (i = 0; i right; d = x->degree; while (A(d) != NULL) ( y = A(d); if (x->n> y->n) ( np = x; x = y; y = np; ) if (y == H1) H1 = x; Fibonnaci_link(H1, y, x); if (x->right == x) H1 = x; A(d) = NULL; d = d + 1; ) A(d) = x; x = x->right; ) while (x != H1); H = NULL; for (int j = 0; j left = A(j); A(j)->right = A(j); if (H != NULL) ( (H->left)->right = A(j); A(j)->right = H; A(j)->left = H->left; H->left = A(j); if (A(j)->n n) H = A(j); ) else ( H = A(j); ) if (H == NULL) H = A(j); else if (A(j)->n n) H = A(j); ) ) ) // Decrease Key Operation int FibonacciHeap::Decrease_key(node *H1, int x, int k) ( node *y; if (H1 == NULL) ( cout << "The Heap is Empty" << endl; return 0; ) node *ptr = Find(H1, x); if (ptr == NULL) ( cout << "Node not found in the Heap"  parent; if (y != NULL && ptr->n n) ( Cut(H1, ptr, y); Cascase_cut(H1, y); ) if (ptr->n n) H = ptr; return 0; ) // Cutting Function int FibonacciHeap::Cut(node *H1, node *x, node *y) ( if (x == x->right) y->child = NULL; (x->left)->right = x->right; (x->right)->left = x->left; if (x == y->child) y->child = x->right; y->degree = y->degree - 1; x->right = x; x->left = x; (H1->left)->right = x; x->right = H1; x->left = H1->left; H1->left = x; x->parent = NULL; x->mark = 'F'; ) // Cascade cut int FibonacciHeap::Cascase_cut(node *H1, node *y) ( node *z = y->parent; if (z != NULL) ( if (y->mark == 'F') ( y->mark = 'T'; ) else ( Cut(H1, y, z); Cascase_cut(H1, z); ) ) ) // Search function node *FibonacciHeap::Find(node *H, int k) ( node *x = H; x->C = 'Y'; node *p = NULL; if (x->n == k) ( p = x; x->C = 'N'; return p; ) if (p == NULL) ( if (x->child != NULL) p = Find(x->child, k); if ((x->right)->C != 'Y') p = Find(x->right, k); ) x->C = 'N'; return p; ) // Deleting key int FibonacciHeap::Delete_key(node *H1, int k) ( node *np = NULL; int t; t = Decrease_key(H1, k, -5000); if (!t) np = Extract_Min(H); if (np != NULL) cout << "Key Deleted" << endl; else cout << "Key not Deleted" << endl; return 0; ) int main() ( int n, m, l; FibonacciHeap fh; node *p; node *H; H = fh.InitializeHeap(); p = fh.Create_node(7); H = fh.Insert(H, p); p = fh.Create_node(3); H = fh.Insert(H, p); p = fh.Create_node(17); H = fh.Insert(H, p); p = fh.Create_node(24); H = fh.Insert(H, p); fh.Display(H); p = fh.Extract_Min(H); if (p != NULL) cout << "The node with minimum key: "    

Complexities

Insertion O(1)
Find Min O(1)
Union O(1)
Extract Min O(log n)
Decrease Key O(1)
Delete Node O(log n)

Fibonacci Heap Applications

  1. To improve the asymptotic running time of Dijkstra's algorithm.

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