Welcome This a note for Zongsi Zhang Leetcode problems Tree (105) Construct Binary Tree from Preorder and Inorder Traversal (109) Convert Sorted List to Binary Search Tree(self balanced) (145) Binary Tree Postorder Traversal DB mysql metadata Data spark & hadoop, learning resources Sahpefile from ESRI Load Binary File with Spark resources RDD, DataFrame and DataSet Solutions to loading small shapefiles Developing on PySpark pygeospark implementation design design modes Simple Factory Pattern Strategy Pattern python python test