C++程式:二叉搜尋樹的左旋操作
二叉搜尋樹是一個排序的二叉樹,其中所有節點都具有以下兩個屬性:
節點的右子樹包含所有大於其父節點鍵值的鍵。
節點的左子樹包含所有小於其父節點鍵值的鍵。每個節點最多隻能有兩個子節點。
樹旋轉是一種操作,它在不改變元素順序的情況下改變二叉樹的結構。它將一個節點向上移動,一個節點向下移動。它用於改變樹的形狀,透過將較小的子樹向下移動,將較大的子樹向上移動來降低其高度,從而提高許多樹操作的效能。旋轉的方向取決於樹節點移動的側邊,也有人說取決於哪個子節點取代根節點。這是一個執行二叉搜尋樹左旋轉的 C++ 程式。
函式描述
height(avl *):計算給定 AVL 樹的高度。
difference(avl *):計算給定樹的子樹高度差。
avl *rr_rotat(avl *):右-右旋轉是右旋轉後接著右旋轉的組合。
avl *ll_rotat(avl *):左-左旋轉是左旋轉後接著左旋轉的組合。
avl *lr_rotat(avl*):左-右旋轉是左旋轉後接著右旋轉的組合。
avl *rl_rotat(avl *):它是右旋轉後接著左旋轉的組合。
avl * balance(avl *):透過獲取平衡因子,對樹執行平衡操作。
avl * insert(avl*, int):執行插入操作。使用此函式在樹中插入值。
show(avl*, int):顯示樹的值。
inorder(avl *):以中序方式遍歷樹。
preorder(avl *):以前序方式遍歷樹。
postorder(avl*):以後序方式遍歷樹。
示例
#include<iostream> #include<cstdio> #include<sstream> #include<algorithm> #define pow2(n) (1 << (n)) using namespace std; struct avl { int d; struct avl *l; struct avl *r; }*r; class avl_tree { public: int height(avl *); int difference(avl *); avl *rr_rotat(avl *); avl *ll_rotat(avl *); avl *lr_rotat(avl*); avl *rl_rotat(avl *); avl * balance(avl *); avl * insert(avl*, int); void show(avl*, int); void inorder(avl *); void preorder(avl *); void postorder(avl*); avl_tree() { r = NULL; } }; int avl_tree::height(avl *t) { int h = 0; if (t != NULL) { int l_height = height(t->l); int r_height = height(t->r); int max_height = max(l_height, r_height); h = max_height + 1; } return h; } int avl_tree::difference(avl *t) { int l_height = height(t->l); int r_height = height(t->r); int b_factor = l_height - r_height; return b_factor; } avl *avl_tree::rr_rotat(avl *parent) { avl *t; t = parent->r; parent->r = t->l; t->l = parent; cout<<"Right-Right Rotation"; return t; } avl *avl_tree::ll_rotat(avl *parent) { avl *t; t = parent->l; parent->l = t->r; t->r = parent; cout<<"Left-Left Rotation"; return t; } avl *avl_tree::lr_rotat(avl *parent) { avl *t; t = parent->l; parent->l = rr_rotat(t); cout<<"Left-Right Rotation"; return ll_rotat(parent); } avl *avl_tree::rl_rotat(avl *parent) { avl *t; t= parent->r; parent->r = ll_rotat(t); cout<<"Right-Left Rotation"; return rr_rotat(parent); } avl *avl_tree::balance(avl *t) { int bal_factor = difference(t); if (bal_factor > 1) { if (difference(t->l) > 0) t = ll_rotat(t); else t = lr_rotat(t); } else if (bal_factor < -1) { if (difference(t->r) > 0) t= rl_rotat(t); else t = rr_rotat(t); } return t; } avl *avl_tree::insert(avl *r, int v) { if (r == NULL) { r= new avl; r->d = v; r->l = NULL; r->r= NULL; return r; } else if (v< r->d) { r->l= insert(r->l, v); r = balance(r); } else if (v >= r->d) { r->r= insert(r->r, v); r = balance(r); } return r; } void avl_tree::show(avl *p, int l) { int i; if (p != NULL) { show(p->r, l+ 1); cout<<" "; if (p == r) cout << "Root -> "; for (i = 0; i < l&& p != r; i++) cout << " "; cout << p->d; show(p->l, l + 1); } } void avl_tree::inorder(avl *t) { if (t == NULL) return; inorder(t->l); cout << t->d << " "; inorder(t->r); } void avl_tree::preorder(avl *t) { if (t == NULL) return; cout << t->d << " "; preorder(t->l); preorder(t->r); } void avl_tree::postorder(avl *t) { if (t == NULL) return; postorder(t ->l); postorder(t ->r); cout << t->d << " "; } int main() { int c, i; avl_tree avl; while (1) { cout << "1.Insert Element into the tree" << endl; cout << "2.show Balanced AVL Tree" << endl; cout << "3.InOrder traversal" << endl; cout << "4.PreOrder traversal" << endl; cout << "5.PostOrder traversal" << endl; cout << "6.Exit" << endl; cout << "Enter your Choice: "; cin >> c; switch (c) { case 1: cout << "Enter value to be inserted: "; cin >> i; r= avl.insert(r, i); break; case 2: if (r == NULL) { cout << "Tree is Empty" << endl; continue; } cout << "Balanced AVL Tree:" << endl; avl.show(r, 1); cout<<endl; break; case 3: cout << "Inorder Traversal:" << endl; avl.inorder(r); cout << endl; break; case 4: cout << "Preorder Traversal:" << endl; avl.preorder(r); cout << endl; break; case 5: cout << "Postorder Traversal:" << endl; avl.postorder(r); cout << endl; break; case 6: exit(1); break; default: cout << "Wrong Choice" << endl; } } return 0; }
輸出
1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 13 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 10 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 15 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 5 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 11 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 4 Left-Left Rotation1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 8 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 16 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 3 Inorder Traversal: 4 5 8 10 11 13 15 16 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 4 Preorder Traversal: 10 5 4 8 13 11 15 16 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 5 Postorder Traversal: 4 8 5 11 16 15 13 10 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 14 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 3 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 7 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 9 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 1 Enter value to be inserted: 52 Right-Right 1.Insert Element into the tree 2.show Balanced AVL Tree 3.InOrder traversal 4.PreOrder traversal 5.PostOrder traversal 6.Exit Enter your Choice: 6
廣告