/*
 *  File:  LargestDeluxe.java
 *
 *  Exercise 2.17 on p.115 of "Java How To Program" (deluxe version):
 *  Find the two largest of an arbitrary number of input characters.
 *  To terminate input, type whatever character your operating system
 *  recognizes as end-of-input (control-D on UNIX or control-Z on DOS).
 *
 *  Copyright:  Northeast Parallel Architectures Center
 *  
 */

import java.io.IOException;

public class LargestDeluxe {

  // Ignore IO exceptions:
  public static void main ( String args[] ) throws IOException {

    int count = 0;                  // character counter
    int currChar;                   // input character
    int largestChar = 0;            // largest input character
    int nextLargestChar = 0;        // next largest input character
    boolean isEndOfInput = false;   // end-of-input flag
    boolean isControlChar;          // control character flag

    // Read and process characters:
    System.out.print( "Enter character #1: " );
    while ( ! isEndOfInput ) {
      // Read a character:
      currChar = System.in.read();
      // The read() method returns -1 if end-of-input is detected:
      isEndOfInput = ( currChar == -1 );
      if ( isEndOfInput ) {
        // Print newline:
        System.out.println( "" );
      } else {
        // Test for control character:
        isControlChar = ( (char) currChar < '\u0020' ) ;
        if ( isControlChar ) {
          if ( (char) currChar == '\n' ) {
            // Prompt for next character:
            System.out.print( "Enter character #" );
            System.out.print( (count + 1) + ": " );
          }
        } else {
          count++;
          if ( currChar > largestChar ) {
            nextLargestChar = largestChar;
            largestChar = currChar;
          } else if ( currChar > nextLargestChar ) {
            nextLargestChar = currChar;
          }
        }
      }
    } // end while loop

    // Output largest character(s):
    if ( count > 0 ) {
      System.out.println( "Largest = " + (char) largestChar );
    }
    if ( count > 1 ) {
      System.out.println( "Next largest = " + (char) nextLargestChar );
    }

  } // end main method

} // end LargestDeluxe class