1. Java Stream
    1. Find index of an element in java list
    2. Find an element in java list
    3. Remove an element in java list
  2. Map
    1. Get all keys in list
    2. Get all values in list
    3. Get value by key
    4. Get key by value
    5. Add a key value in map
    6. Remove a key value
    7. Check if key is present in Map
    8. Check if value is present in Map