2Sigma OA prepare: Longest Chain

DP use HashMap: 根據string的長度sort，然后維護每個string的longest chain，default為1，如果刪除某個char生成的string能提供更長的cha ...

Amazon | OA 2019 | Optimal Utilization

2-Pointers Syntax side: Pay attention to how to print an array: System.out.println(Arra ...