题解 | #二叉树的后序遍历#

/**
 * 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
 */
 static int arr[101];
 static int size=0;
 void Postorder(struct TreeNode* root){
    if(root==NULL){

    }else{
        Postorder(root->left);
        Postorder(root->right);
        arr[size++]=root->val;
    }
 }
int* postorderTraversal(struct TreeNode* root, int* returnSize ) {
    // write code here
    Postorder(root);
    *returnSize=size;
    return arr;
}