- usefulness of hash table, where it can slash time compexity of almost all algorithm more than half (if used properly)
- lecture : https://www.youtube.com/watch?v=bFLJgycI1zk&t=1709s
- show topbottom & bottomup can reduce time complexity of an algorithm
- lecture : https://www.youtube.com/watch?v=RZb-MQlW3uw&t=1189s
credit : shopee code league & rocketacademy