非递归中序遍历二叉树c

非递归中序遍历二叉树的代码如下：

void inorderTraversal(TreeNode* root) {
stack<TreeNode*> s;
TreeNode* curr = root;
while (curr != NULL || !s.empty()) {
while (curr != NULL) {
s.push(curr);
curr = curr->left;
}
curr = s.top();
s.pop();
cout << curr->val << " ";
curr = curr->right;
}
}

其中，stack是用来存储节点的栈，curr是当前遍历到的节点。首先将根节点压入栈中，然后遍历其所有左子节点并依次压入栈中，直到没有左子节点为止。然后取出栈顶元素，输出其值，将curr指向其右子节点。重复上述过程，直到所有节点都被遍历完毕。

相关问题

c++实现非递归中序遍历二叉树

以下是C++实现非递归中序遍历二叉树的代码：

#include <iostream>
#include <stack>
using namespace std;

struct TreeNode {
    int val;
    TreeNode* left;
    TreeNode* right;
    TreeNode(int x) : val(x), left(NULL), right(NULL) {}
};

void inorderTraversal(TreeNode* root) {
    stack<TreeNode*> s;
    TreeNode* cur = root;
    while (cur != NULL || !s.empty()) {
        while (cur != NULL) {
            s.push(cur);
            cur = cur->left;
        }
        cur = s.top();
        s.pop();
        cout << cur->val << " ";
        cur = cur->right;
    }
}

int main() {
    TreeNode* root = new TreeNode(1);
    root->right = new TreeNode(2);
    root->right->left = new TreeNode(3);
    inorderTraversal(root); // 输出：1 3 2
    return 0;
}

二叉树非递归中序遍历C语言实现

以下是二叉树非递归中序遍历的C语言实现：

// 定义二叉树结构体
typedef struct TreeNode {
    int val;
    struct TreeNode* left;
    struct TreeNode* right;
} TreeNode;

// 定义栈结构体
typedef struct Stack {
    TreeNode** arr;
    int top;
    int maxSize;
} Stack;

// 创建栈
Stack* createStack(int size) {
    Stack* stack = (Stack*)malloc(sizeof(Stack));
    stack->arr = (TreeNode**)malloc(sizeof(TreeNode*) * size);
    stack->top = -1;
    stack->maxSize = size;
    return stack;
}

// 入栈
void push(Stack* stack, TreeNode* node) {
    if (stack->top == stack->maxSize - 1) {
        return;
    }
    stack->arr[++stack->top] = node;
}

// 出栈
TreeNode* pop(Stack* stack) {
    if (stack->top == -1) {
        return NULL;
    }
    return stack->arr[stack->top--];
}

// 判断栈是否为空
int isEmpty(Stack* stack) {
    return stack->top == -1;
}

// 中序遍历
int* inorderTraversal(TreeNode* root, int* returnSize) {
    *returnSize = 0;
    int* res = (int*)malloc(sizeof(int));
    Stack* stack = createStack(100); // 创建栈
    TreeNode* cur = root;
    while (cur != NULL || !isEmpty(stack)) {
        while (cur != NULL) { // 遍历左子树并入栈
            push(stack, cur);
            cur = cur->left;
        }
        cur = pop(stack); // 左子树遍历完毕，出栈一个节点
        res = (int*)realloc(res, sizeof(int) * (*returnSize + 1));
        res[(*returnSize)++] = cur->val; // 将出栈节点的值加入结果数组
        cur = cur->right; // 遍历右子树
    }
    return res;
}

该实现利用栈来模拟递归的过程，将待遍历的节点入栈，遍历完左子树后出栈一个节点，将其值加入结果数组，然后遍历其右子树。重复以上步骤直到栈为空。