二叉树链式存储结构代码实现
上一篇博客已经介绍过实际内容了，这一篇直接上干货代码了。
结构体
前面写的是用c语言写的，用的也是递归的方法
typedef char BTDataType;
typedef struct BTNode
{
struct BTNode* left;
struct BTNode* right;
BTDataType data;
}BTNode;
1、创建二叉树
typedef struct ReturnType{
BTNode *root;
int used;
}ReturnType;
// 1. 创建二叉树
ReturnType CreateBinTree(BTDataType* array, int size)
{
BTDataType rootValue = array[0];
if (rootValue == '#')
{
ReturnType returnValue;
returnValue.root = NULL;
returnValue.used = 1;
return returnValue;
}
BTNode *root = (BTNode*)malloc(sizeof(BTNode));
root->data = rootValue;
ReturnType left = CreateBinTree(array + 1 + left.used, size - 1 - left.used);
ReturnType right = CreateBinTree(array + 1 + left.used, size - 1 - left.used);
root->left = left.root;
root->right = right.root;
ReturnType returnValue;
returnValue.root = root;
returnValue.used = 1 + left.used + right.used;
return returnValue;
}
2、拷贝二叉树
// 拷贝二叉树
BTNode* CopyBinTree(BTNode* pRoot)
{
if (pRoot == NULL)
{
return NULL;
}
BTNode *root = (BTNode*)malloc(sizeof(BTNode));
root->data = pRoot->data;
root->left = CopyBinTree(pRoot->left);
root->right = CopyBinTree(pRoot->right);
return root;
}
3、销毁二叉树
// 销毁二叉树
void DestroyBinTree(BTNode* pRoot)
{
if (pRoot != NULL)
{
if (pRoot != NULL)
{
pRoot = NULL;
}
if (pRoot->left != NULL)
{
DestroyBinTree(pRoot->left);
pRoot->left = NULL;
}
if (pRoot->right != NULL)
{
DestroyBinTree(pRoot->right);
pRoot->right = NULL;
}
}
}
4、二叉树的三种遍历方式 （递归方式）
// 前序遍历
void PreOrder(BTNode* pRoot)
{
if (pRoot == NULL)
{
return;
}
printf("%d", pRoot->data);
PreOrder(pRoot->left);
PreOrder(pRoot->right);
//中序遍历
void InOrder(BTNode* pRoot)
{
if (pRoot == NULL)
{
return;
}
InOrder(pRoot->left);
printf("%d", pRoot->data);
InOrder(pRoot->right);
}
//后序遍历
void PostOrder(BTNode* pRoot)
{
if (pRoot == NULL)
{
return;
}
PostOrder(pRoot->left);
PostOrder(pRoot->right);
printf("%d", pRoot->data);
}
5、获取二叉树中节点的个数
// 获取二叉树中节点的个数
int GetNodeCount(BTNode* pRoot)
{
if (pRoot == NULL)
{
return 0;
}
int left = GetLeafNodeCount(pRoot->left);
int right = GetLeafNodeCount(pRoot->right);
return left + right + 1;
}
6、求二叉树的高度
// 求二叉树的高度
int Max(int a, int b)
{
return a > b ? a : b;
}
int Height(BTNode* pRoot)
{
if (pRoot == NULL)
{
return 0;
}
int left = Height(pRoot->left);
int right = Height(pRoot->right);
return Max(left, right) + 1;
}
7、检测二叉树是否平衡（用了两种方法，由于方法的不同，时间复杂度也是不同的）
// 检测二叉树是否平衡O(N^2) }
//求树的深度
int getDepth(BTNode *pRoot)
{
if (pRoot == NULL)
{
return 0;
}
int left = getDepth(pRoot->left);
int right = getDepth(pRoot->right);
return Max(left, right) + 1;
}
bool IsBalanceTree(BTNode* pRoot)
{
if (pRoot == NULL)
{
return true;
}
if (IsBalanceTree(pRoot->left) == false)
{
return false;
}
if (IsBalanceTree(pRoot->right) == false)
{
return false;
}
int left = getDepth(pRoot->left);
int right = getDepth(pRoot->right);
int diff = left - right;
if (diff<-1 || diff>1)
{
return false;
}
return true;
}
// 检测二叉树是否平衡O(N)
int max(int *a, int *b)
{
return *a > *b ? *a : *b;
}
bool IsBalanceTree_P(BTNode* pRoot, int* height)
{
if (pRoot == NULL)
{
height = 0;
return 0;
}
int *heightLeft;
bool resultLeft = IsBalanceTree_P(pRoot->left, heightLeft);
int *heightRight;
bool resultRight = IsBalanceTree_P(pRoot->right, heightRight);
if (resultLeft && resultRight && abs(heightLeft - heightRight) <= 1) {
*height = max(heightLeft, heightRight) + 1;
return true;
}
else {
*height = max(heightLeft, heightRight) + 1;
return false;
}
}
8、获取二叉数中叶子节点的个数
// 获取二叉数中叶子节点的个数
int GetLeafNodeCount(BTNode* pRoot)
{
if (pRoot == NULL)
{
return 0;
}
else if (pRoot->left == NULL && pRoot->right == NULL)
{
return 1;
}
else
{
int left = GetLeafNodeCount(pRoot->left);
int right = GetLeafNodeCount(pRoot->right);
return left + right ;
}
}
9、 获取二叉树第K层节点的个数
// 获取二叉树第K层节点的个数
int GetKLevelNodeCount(BTNode* pRoot, int k)
{
assert(k >= 1);
if (pRoot == NULL)
{
return 0;
}
else if (k == 1)
{
return 1;
}
else
{
return GetKLevelNodeCount(pRoot->left, k - 1) + GetKLevelNodeCount(pRoot->right, k - 1);
}
}
10、获取二叉树中某个节点的双亲节点
// 获取二叉树中某个节点的双亲节点
BTNode* GetNodeParent(BTNode* pRoot, BTNode* pNode)
{
assert(pRoot != NULL);
BTNode *root = pRoot;
if (root->data == pNode->data)
{
return NULL;
}
if (pRoot->left != NULL || pRoot->right != NULL)
{
if (pRoot->left->data == pNode->left->data || pRoot->right->data == pNode->right->data)
{
return pRoot;
}
else
{
return GetNodeParent(pRoot->left, pNode);
return GetNodeParent(pRoot->right, pNode);
}
}
return NULL;
}
11、求二叉树的镜像
// 求二叉树的镜像
void Mirror(BTNode* pRoot)
{
if (pRoot != NULL)
{
if (pRoot->left != NULL && pRoot->right != NULL)
{
BTNode *temp = pRoot->left;
pRoot->left = pRoot->right;
pRoot->right = temp;
Mirror(pRoot->left);
Mirror(pRoot->right);
}
}
}
12、二叉树的三种遍历方式 （非递归方式）因为要用到堆栈所以使用c++写的
//前序遍历
#include //中序遍历
void InOrderNor(BTNode* pRoot)
{
BTNode* cur = pRoot;
std::stack<BTNode*> st;
while (cur != NULL || !st.empty())
{
while (cur != NULL)
{
st.push(cur);
cur = cur->left;
}
BTNode *top = st.top();
printf("%d", cur->data);
st.pop();
cur = top->right;
}
}
//后序遍历
void PostOrderNor(BTNode* pRoot)
{
BTNode* cur = pRoot;
BTNode* last = NULL;
std::stack<BTNode*> st;
while (cur != NULL || !st.empty())
{
while (cur != NULL)
{
st.push(cur);
cur = cur->left;
}
BTNode *top = st.top();
if (top->right == NULL || top->right == last)
{
st.pop();
printf("%d", cur->data);
last = top;
}
else
{
cur = top->right;
}
}
}
13、层序遍历
//层序遍历
#include