题解 | #二叉树的后序遍历#

递归后序遍历

/**
 * struct TreeNode {
 *	int val;
 *	struct TreeNode *left;
 *	struct TreeNode *right;
 * };
 */
/**
 * 代码中的类名、方法名、参数名已经指定，请勿修改，直接返回方法规定的值即可
 *
 * 
 * @param root TreeNode类 
 * @return int整型一维数组
 * @return int* returnSize 返回数组行数
 */
#include <stdlib.h>
int count = 0;
void postOrder(struct TreeNode* root,int* resul){
    if(root!=NULL){
        postOrder(root->left,resul);
        postOrder(root->right,resul);
        resul[count++] = root->val;
    }
}
int* postorderTraversal(struct TreeNode* root, int* returnSize ) {
    // write code here
    int* resul_li = (int* )malloc(sizeof(int)*101);
    postOrder(root,resul_li);
    *returnSize = count;
    return resul_li;
}