Problem 3 (A Grade): Radio Difference As a radio network baron, you are always in the lookout to cut corners and save money. If two radio stations are playing similar play-lists, then you can save money by eliminating one of the radio stations or aiming it at a different demographic. You need to determine which of your stations are too similar. The difference between two radio stations is defined as the sum of squares of the differ- ences between the ratings of the song ratings. That is, all radio stations have the same set of songs, each with their own ratings. Suppose the ratings for the songs at radio station U are u0, u1, u2,....uN, and the ratings for the same songs at radio station V are v0, v1, v2... vN, where ui and vi are ratings for the same song at the respective radio stations. Then the dierence between the two radio stations is: D(U; V ) = (u0 - v0)2 + (u1 -v1)2 + (u2 -v2)2 + ... + (uN - vN)2 If D(U; V ) is smaller than the specifed similarity threshold, then the two radio stations are too similar. Given a list of songs, and sequences of daily song requests for your radio stations, your program will need to determine if each pair of radio stations is too similar. Write a program called RadioDifference.java that reads in a song list, a list of radio stations, a sequence of song requests, and a similarity threshold. The program outputs all pairs of radio stations whose difference is less than the similarity threshold after all the requests in each day have been processed. Input

The input comprises a number of lines. The first line, contains an integer N, denoting the number of songs in the song list. This is followed by N lines, enumerating the songs. Each line consists of three values: a single word, denoting the title of the song; an integer T, denoting the length of the song (in seconds); and decimal value between 0 and 1 denoting the initial popularity of the song. For example: Red_Barchetta 371 0.5 The next line contains three values: an integer T, denoting the maximum length (in minutes) of the play-list, a double W denoting the weight attributed to new requests (see the formula above); and an integer D denoting the number of days of song requests to follow. For example, 22 0.5 2 species a T = 22 minute play-list, with a weight W = 0:5, and D = 2 days of song requests. Each day of requests consists of a number of lines. The first line contains the integer R, denoting the number of song requests to follow. The next R lines contain song titles from the previously loaded song list.The song list is followed by three numbers (not two): an integer S, denoting the number of radio stations; an integer D, denoting the number of days of requests; and lastly, a double X, denoting the the similarity threshold. Please see full example below. Processing The processing is the same as in Problem 2 except that no play-lists are generated. Once all requests are processed, the difference for each pair of stations is computed and all pairs of stations whose difference is below the similarity threshold are displayed. Each pair that is displayed should only be displayed once, and the order of the stations should match the input order. Output For each pair of stations whose difference is below the similarity threshold, output the line Difference between U and V is below threshold where U and V are the station identifiers of the two stations. Note, that U must come before V in the radio station list. See next section for example of output. Example Sample Input 13 The_Garden 419 0.7 Red_Sector_A 311 0.6 High_Water 333 0.4 Red_Barchetta 371 0.5 The_Pass 291 0.55 Roll_The_Bones 330 0.45 Arm_And_Sword 396 0.55 Test_For_Echo 356 0.35 Vapor_Trails 358 0.34 Nobodys_Hero 349 0.22 2112_Overture 1232 0.7 Closer_To_The_Heart 175 0.9 Cygnus_X_1 622 0.2 3 1 0.2 CBC 22 0.5 CBC1 22 0.5 CBC2 22 0.5 5 CBC Red_Sector_A CBC1 Red_Sector_A CBC2 Vapor_Trails CBC Red_Sector_A CBC Test_For_Echo Sample Output Difference between CBC and CBC1 is below threshold