Challenge 7

26/02/26 09:19
package net.p3consulting.so.challenges;

// https://stackoverflow.com/beta/challenges/79767716/challenge-7-pangram-checker-completed

import org.json.JSONArray;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.regex.Pattern;

public class Challenge7 {

  private static String readFile(final String filePath) {
    final InputStream is = Challenge14.class.getResourceAsStream(filePath);
    final ByteArrayOutputStream baos = new ByteArrayOutputStream();
    String content ;
    try {
      byte[] byteChunk = new byte[4096];
      int n;

      while ((n = is.read(byteChunk)) > 0) {
        baos.write(byteChunk, 0, n);
      }

      content = baos.toString(StandardCharsets.UTF_8.name());
    }
    catch (final IOException e) {
      throw new RuntimeException(e);
    }

    return content ;
  }

  protected static void solve(final JSONArray problems) {
    final Pattern checkPangram = Pattern.compile("a+b+c+d+e+f+g+h+i+j+k+l+m+n+o+p+q+r+s+t+u+v+w+x+y+z+");

    problems.forEach(
        s -> {
          final String stripped = ((String)s).toLowerCase().replaceAll("[^a-z]", "") ;
          char chars[] = new char[stripped.length()];

          stripped.getChars(0, stripped.length(), chars, 0);
          Arrays.sort(chars);

          final String sorted = new String(chars);
          final boolean perfectPangram = "abcdefghijklmnopqrstuvwxyz".equals(sorted);
          final boolean pangram = perfectPangram || (sorted.length() > 26 && checkPangram.matcher(sorted).matches());

          System.out.println(String.format("'%s'; isPangram %b; isPerfectPangram %b",s,
              pangram, perfectPangram));
        }
    );
  }

  public static void main(final String[] args) {
    final String classPath = System.getProperty("java.class.path", ".");
    final String[] classPathElements = classPath.split(System.getProperty("path.separator"));

    final File dir = new File(classPathElements[0]);
    final Pattern pattern = Pattern.compile(".*/challenge7_\\d+.json");
    Arrays.stream(dir.listFiles()).sorted().forEach(
        file -> {
          String fileName = null;
          try {
            fileName = file.getCanonicalPath();
            if (pattern.matcher(fileName).matches()) {
              fileName = fileName.substring(fileName.lastIndexOf('/'));
              System.out.println(fileName);

              JSONArray problems = new JSONArray( readFile(fileName) );

              solve(problems);
            }
          }
          catch (IOException ex) {
            throw new RuntimeException(ex);
          }
        }
    ) ;
  }
}