In Java

Write a method countMajors(String filename) that reads the data in filename and returns a Map as described above. Feel free to use the built-in Java map classes (java.util.HashMap, java.util.TreeMap) in your solution. You can assume that each line of the data file is formatted like this:

lastname,firstname,major

Heres an example of a situation thats well-suited for using the map data structure. Suppose you have a data file of students at a university, and youre trying to figure out how many students are in each major. You can read the file and parse the information into a map, where the keys are the majors and the values are the counts of how many students are in that major.