package edu.princeton.cs.algs4.ch51; import edu.princeton.cs.introcs.*; /************************************************************************* * Compilation: javac Count.java * Execution: java Count alpha < input.txt * * Create an alphabet specified on the command line, read in a * sequence of characters over that alphabet (ignoring characters * not in the alphabet), computes the frequency of occurrence of * each character, and print out the results. * * % java Count ABCDR < abra.txt * A 5 * B 2 * C 1 * D 1 * R 2 * * % java Count 0123456789 < pi.txt * 0 99959 * 1 99757 * 2 100026 * 3 100230 * 4 100230 * 5 100359 * 6 99548 * 7 99800 * 8 99985 * 9 100106 * *************************************************************************/ public class Count { public static void main(String[] args) { Alphabet alpha = new Alphabet(args[0]); int R = alpha.R(); int[] count = new int[R]; String a = StdIn.readAll(); int N = a.length(); for (int i = 0; i < N; i++) if (alpha.contains(a.charAt(i))) count[alpha.toIndex(a.charAt(i))]++; for (int c = 0; c < R; c++) StdOut.println(alpha.toChar(c) + " " + count[c]); } } /************************************************************************* * Copyright 2002-2012, Robert Sedgewick and Kevin Wayne. * * This file is part of algs4-package.jar, which accompanies the textbook * * Algorithms, 4th edition by Robert Sedgewick and Kevin Wayne, * Addison-Wesley Professional, 2011, ISBN 0-321-57351-X. * http://algs4.cs.princeton.edu * * * algs4-package.jar is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * algs4-package.jar is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * You should have received a copy of the GNU General Public License * along with algs4-package.jar. If not, see http://www.gnu.org/licenses. *************************************************************************/