COS126

• Download FrequencyTable.java

/*****************************************************************************
 * Name:                                                                     *
 * Login:                                                                    *
 * Precept:                                                                  *
 *                                                                           *
 * Description: Counts the repeated occurrences in a list of Strings.        *
 *                                                                           *
 * Example:                                                                  *
 * % java-introcs FrequencyTable                                             *
 * duck duck goose[Ctrl+D]                                                   *
 * 2 duck                                                                    *
 * 1 goose                                                                   *
 *                                                                           *
 * Remarks:                                                                  *
 *  - This is book exercise 4.4 #36 (Booksite Creative Ex 4.4 #5)            *
 *  - Use with mobydick.txt, available on the precepts page.                 *
 *****************************************************************************/

public class FrequencyTable {

       // maintain counts of all words seen so far
       // the key is the word and the value is the count
       private ST<_______________> st = _________________________;
   
       // remark: we have not declared a constuctor! but Java lets every class 
       // have a no-argument constructor by default. It only runs the line of 
       // code above (instance variable initialization).
   
       // increment the frequency of this word
       public void click(String word) {
           int count = count(word);
           st.put(word, count + 1);
       }
   
       // what is the frequency of this word?
       public int count(String word) {
           if (!st._____(___________)) return 0;  // if word is not in ST
           else return _____.______(__________);  // get word's count
       }
   
       // print out all words and their frequencies
       public void show() {

           // remark: this is called a "foreach loop" or an "enhanced for loop."
           // it goes through all keys in alphabetical order. this is the only
           // way to traverse a symbol table!

           for (String word : st) {
               // print out frequency and word, separated by a space
               StdOut.println(_______________(______) + " " + ___________);
           }
       }
   
       // count all words in StdIn
       public static void main(String[] args) {
   
           FrequencyTable freq = new FrequencyTable();

           // build frequency table from words on standard input
           while (!StdIn.isEmpty()) {
               String word = StdIn.readString();
               freq.________(word);
           }
   
           // print frequency table to standard output
           freq.show();
       }
}