题解 | #二叉树的后序遍历#

int result[100];
int* postorderTraversal(struct TreeNode* root, int* returnSize ) ;

void find(struct TreeNode* root, int* returnSize,int* result)
{
    if(root->left) find(root->left, returnSize,result);
    if(root->right) find(root->right, returnSize,result);
    result[(*returnSize)++]=root->val;
}

int* postorderTraversal(struct TreeNode* root, int* returnSize ) {
    // write code here
    *returnSize=0;
    if(!root) return returnSize;
    find(root,returnSize,result);
    return result;
}