Description

1) (30 points) desgin functions to inserts a (key, value) pair into the HashMap. If the key alreadyexists in the map, update the corresponding value.
2) (30 points) int get(int key) returns the value to which the specified key is mapped, or -1 if thismap contains no mapping for the key
3) (40 points) void remove(key) removes the key and its corresponding value if the mapcontains the mapping for the key
Note: please analyze your time complexity for each function. You can wirte it as the comment or the function description.
Please do a simple test of all your methods once you finish it.