7. CountSubstrings Method Header: public static int countSubstrings (String sequence, String word) Problem Description: We want to find how many times a sequence appears in a particular word. For example, in the word "banana", the sequence "na" appears two times, with "baNAna" and "banaNA". We also have "ana" appear two times, being "bANAna" and "banANA" - note that this means that we can have overlaps between the starts of our sequences (this actually makes the problem easier!) Invariants: You may assume that neither sequence nor word are null, and that both have positive lengths (0 is not positive.) You may also assume that the strings are both all lowercase. Hint: The function String.substring(x, y) will be helpful here. //Example: String className = "cis110"; String department = className.substring(0, 3); String number = className.substring(3, className.length()); System.out.println(department); // prints "cis" System.out.println(number); // prints "110"