二叉树-C语言

struct TreeNode {
    char val;
    struct TreeNode *left;
    struct TreeNode *right;
};

void PreOrderTraverse(struct TreeNode * T){
    if(T!=NULL){
        printf("%c", T->val);
        PreOrderTraverse(T->left);
        PreOrderTraverse(T->right);
    }
}
void InOrderTraverse(struct TreeNode * T){
    if(T!=NULL){
        InOrderTraverse(T->left);
        printf("%c", T->val);
        InOrderTraverse(T->right);
    }
}
void PostOrderTraverse(struct TreeNode * T){
    if(T!=NULL){
        PostOrderTraverse(T->left);
        PostOrderTraverse(T->right);
        printf("%c", T->val);
    }
}

//中序迭代打印二叉树
//左右均未被访问，入站
//站中节点都是左访问右未
void InOderIteration(struct TreeNode * T){
    stack<struct TreeNode *> stk;
    struct TreeNode *p = T;
    while(p!=NULL || !stk.empty()){
        while (p!=NULL) {
            stk.push(p);
            p = p -> left;
        }
        p = stk.top();
        stk.pop();
        printf("%c", p->val);
        p = p -> right;
    }
}

struct TreeNode * CreatBinTree(){
    char ch;
    scanf("%c",&ch);
    if(ch == '#') return NULL;
    else{
        struct TreeNode * T = (struct TreeNode *)malloc(sizeof(struct TreeNode));
        T -> val = ch;
        T -> left = CreatBinTree();
        T -> right = CreatBinTree();
        return T;
    }
}

//先序复制二叉树
struct TreeNode * CopyBinTree (struct TreeNode * T){
    if(T==NULL) return NULL;
    else{
        struct TreeNode * NewT = (struct TreeNode *)malloc(sizeof(struct TreeNode));
        NewT -> val = T->val;
        NewT -> left = CopyBinTree(T -> left);
        NewT -> right = CopyBinTree(T -> right);
        return NewT;
    }
}
//计算二叉树的深度
int DepthBinTree(struct TreeNode * T){
    if( T== NULL) return 0;
    else{
        int DepthLeft = DepthBinTree(T->left);
        int DepthRight = DepthBinTree(T->right);
        return 1 + fmax(DepthLeft, DepthRight);
    }
}
//计算节点个数
int NodeCount(struct TreeNode * T){
    if(T==NULL) return 0;
    else{
        return 1 + NodeCount(T->left) + NodeCount(T->right);
    }
}

void PrintBinTree(struct TreeNode * T){
    printf("PreOerderTraverse:");
    PreOrderTraverse(T);
    printf("\n");
    
    printf("InOrderTraverse:");
    InOrderTraverse(T);
    printf("\n");
    
    printf("PostOrderTraverse:");
    PostOrderTraverse(T);
    printf("\n");
    
    printf("InOderIteration:");
    InOderIteration(T);
    printf("\n");
}

int main() {

    
    struct TreeNode * T = NULL;
    T = CreatBinTree();

    PrintBinTree(T);
    
    //复制一颗二叉树
    struct TreeNode * NewT = NULL;
    NewT = CopyBinTree(T);
    
    PrintBinTree(NewT);
    
    printf("二叉树的深度：%d\n", DepthBinTree(T));
    printf("二叉树的节点个数：%d\n", NodeCount(T));
    return 0;
}