1.在二叉树中查询含有val的结点
BTNode* FindValue(BTNode* ptr, ElemType val) //在二叉树中查询含有val的结点
{
if (ptr == nullptr || ptr->data == val)
{
return ptr;
}
else
{
BTNode * p = FindValue(ptr->leftchild, val); //左边找不到 就找右边
if (nullptr == p)
{
p = FindValue(ptr->rightchild, val);
}
return p;
}
}
2.二叉树找双亲结点
BTNode* FindParent(BTNode* ptr, BTNode* child) //找双亲
{
if (nullptr == ptr || ptr-leftchild==child || ptr->rightchild == child)
{
return ptr;
}
else
{
BTNode* p = FindParent(ptr->leftchild, child);
if (nullptr == p)
{
p = FindParent(ptr->rightchild, child);
}
return p;
}
}
3.计算二叉树中结点的个数
int GetSize(BTNode* ptr) //计算二叉树中结点的个数
{
if (nullptr == ptr)
return 0;
else
return GetSize(ptr->leftchild) + GetSize(ptr->rightchild) + 1;
} //左孩子结点的个数+右孩子结点的个数+1
4.计算二叉树的高度
int Max(int a, int b) //找高度大的加一
{
return a > b ? a : b;
}
int GetDepth(BTNode* ptr) //二叉树的高度
{
if (nullptr == ptr)
return 0;
else
return Max(GetDepth(ptr->leftchild), GetDepth(ptr->rightchild)) + 1;
}
5.前序非递归遍历
void NicePreOrder(BTNode* ptr) //前序非递归遍历
{
if (nullptr == ptr) return; //空树
std::stack st; //将栈的地址压入进去
st.push(ptr); //将ptr入栈
while (!st.empty())
{
ptr = st.top(); st.pop();
printf("%c ", ptr->data);
if (ptr->rightchild != nullptr) //
{
st.push(ptr->rightchild);
}
if (ptr->leftchild != nullptr)
{
st.push(ptr->leftchild);
}
}
printf("\n");
}
6.二叉树层次遍历
void NiceLevelOrder(BTNode* ptr) //层次遍历
{
if (nullptr == ptr) return;
std::queue qu;
qu.push(ptr);
while (!qu.empty())
{
ptr = qu.front; qu.pop();
printf("%c", ptr->data);
if (ptr->leftchild != nullptr)
{
qu.push(ptr->leftchild);
}
if (ptr->rightchild != nullptr)
{
qu.push(ptr->rightchild);
}
}
}
7.判断是否为满二叉树
bool IsFullBinarTree(BTNode* ptr) //判断是否满二叉树
{
bool res = true;
if (nullptr = ptr) return res;
int sum = 1;
std::queuequ;
qu.push(ptr);
while (!qu.empty())
{
for (int i = 0; i < sum; ++i)
{
ptr = qu.front; qu.pop();
if (ptr->leftchild != nullptr)qu.push(ptr->leftchild);
if (ptr->rightchild != nullptr)qu.push(ptr->rightchild);
}
sum += sum;
if (qu.size() == 0) break;
if (qu.size() != sum)
{
res = false;
break;
}
}
return res;
}
总代码如下：
#include
#include
#include
#include
#include // using namespace std;
#include
typedef char ElemType;
typedef struct BTNode //BinaryTreeNode
{
struct BTNode* leftchild;
struct BTNode* rightchild;
ElemType data;
}BTNode, * BinaryTree;
typedef struct
{
BTNode* pnode;
int popnum;
}StkNode;
BTNode* Buynode(ElemType val, BTNode* Larg = nullptr, BTNode* Rarg = nullptr)
{
BTNode* s = (BTNode*)malloc(sizeof(BTNode));
if (nullptr == s) exit(EXIT_FAILURE);
s->data = val;
s->leftchild = Larg;
s->rightchild = Rarg;
return s;
}
void Freenode(BTNode* p)
{
free(p);
}
void PreOrder(BTNode* ptr)
{
if (ptr != nullptr)
{
printf("%c ", ptr->data);
PreOrder(ptr->leftchild);
PreOrder(ptr->rightchild);
}
}
void InOrder(BTNode* ptr)
{
if (ptr != nullptr)
{
InOrder(ptr->leftchild);
printf("%c ", ptr->data);
InOrder(ptr->rightchild);
}
}
void PastOrder(BTNode* ptr)
{
if (ptr != nullptr)
{
PastOrder(ptr->leftchild);
PastOrder(ptr->rightchild);
printf("%c ", ptr->data);
}
}
BTNode* CreateBinaryTree()
{
ElemType ch;
BTNode* s = nullptr;
scanf_s("%c", &ch);
if (ch != '#')
{
s = Buynode(ch);
s->leftchild = CreateBinaryTree();
s->rightchild = CreateBinaryTree();
}
return s;
}
BTNode* CreateBinaryTree(const char** p)
{
BTNode* s = nullptr;
if (p != nullptr && *p != nullptr && **p != '#')
{
s = Buynode(**p);
s->leftchild = CreateBinaryTree(&++ * p);
s->rightchild = CreateBinaryTree(&++ * p);
}
return s;
}
int FindIs(const char* is, const char ch, int n)
{
int pos = -1;
for (int i = 0; i < n; ++i)
{
if (is[i] == ch)
{
pos = i;
break;
}
}
return pos;
}
BTNode* CreatePI(const char* ps, const char* is, int n)
{
BTNode* s = nullptr;
if (n > 0)
{
s = Buynode(ps[0]);
int pos = FindIs(is, ps[0], n);
if (-1 == pos) exit(EXIT_FAILURE);
s->leftchild = CreatePI(ps + 1, is, pos);
s->rightchild = CreatePI(ps + pos + 1, is + pos + 1, n - pos - 1);
}
return s;
}
BTNode* CreateBinaryTreePI(const char* ps, const char* is)
{
assert(ps != nullptr && is != nullptr);
int n = strlen(ps);
return CreatePI(ps, is, n);
}
BTNode* FindValue(BTNode* ptr, ElemType val) //在二叉树中查询含有val的结点
{
if (ptr == nullptr || ptr->data == val)
{
return ptr;
}
else
{
BTNode * p = FindValue(ptr->leftchild, val); //左边找不到 就找右边
if (nullptr == p)
{
p = FindValue(ptr->rightchild, val);
}
return p;
}
}
BTNode* Parent(BTNode* ptr, BTNode* child)
{
if (nullptr == ptr || ptr->leftchild == child || ptr->rightchild == child)
{
return ptr;
}
else
{
BTNode* p = Parent(ptr->leftchild, child);
if (nullptr == p)
{
p = Parent(ptr->rightchild, child);
}
return p;
}
}
BTNode* FindParent(BTNode* ptr, BTNode* child) //找双亲
{
if (nullptr == ptr || ptr-leftchild==child || ptr->rightchild == child)
{
return ptr;
}
else
{
BTNode* p = FindParent(ptr->leftchild, child);
if (nullptr == p)
{
p = FindParent(ptr->rightchild, child);
}
return p;
}
}
int GetSize(BTNode* ptr) //计算二叉树中结点的个数
{
if (nullptr == ptr)
return 0;
else
return GetSize(ptr->leftchild) + GetSize(ptr->rightchild) + 1;
} //左孩子结点的个数+右孩子结点的个数+1
int Max(int a, int b) //找高度大的加一
{
return a > b ? a : b;
}
int GetDepth(BTNode* ptr) //二叉树的高度
{
if (nullptr == ptr)
return 0;
else
return Max(GetDepth(ptr->leftchild), GetDepth(ptr->rightchild)) + 1;
}
void NicePreOrder(BTNode* ptr) //前序非递归遍历
{
if (nullptr == ptr) return; //空树
std::stack st; //将栈的地址压入进去
st.push(ptr); //将ptr入栈
while (!st.empty())
{
ptr = st.top(); st.pop();
printf("%c ", ptr->data);
if (ptr->rightchild != nullptr) //
{
st.push(ptr->rightchild);
}
if (ptr->leftchild != nullptr)
{
st.push(ptr->leftchild);
}
}
printf("\n");
}
void NiceLevelOrder(BTNode* ptr) //层次遍历
{
if (nullptr == ptr) return;
std::queue qu;
qu.push(ptr);
while (!qu.empty())
{
ptr = qu.front; qu.pop();
printf("%c", ptr->data);
if (ptr->leftchild != nullptr)
{
qu.push(ptr->leftchild);
}
if (ptr->rightchild != nullptr)
{
qu.push(ptr->rightchild);
}
}
}
bool IsFullBinarTree(BTNode* ptr) //判断是否满二叉树
{
bool res = true;
if (nullptr = ptr) return res;
int sum = 1;
std::queuequ;
qu.push(ptr);
while (!qu.empty())
{
for (int i = 0; i < sum; ++i)
{
ptr = qu.front; qu.pop();
if (ptr->leftchild != nullptr)qu.push(ptr->leftchild);
if (ptr->rightchild != nullptr)qu.push(ptr->rightchild);
}
sum += sum;
if (qu.size() == 0) break;
if (qu.size() != sum)
{
res = false;
break;
}
}
return res;
}
int main()
{
BinaryTree root = nullptr;
const char* ps = "ABCDEFGH";
const char* is = "CBEDFAGH";
const char* ls = "CEFDBHGA";
root = CreateBinaryTreePI(ps, is);
InOrder(root);
printf("\n");
BTNode* p = FindValue(root, 'D');
if (p != nullptr)
{
printf("Node addr : %p val: %c \n", p, p->data);
}
else
{
printf("find not value \n");
}
printf("node size: %d \n", GetSize(root));
NicePreOrder(root);
NiceLevelOrder(root);
return 0;
}
