/**
 * CheckFile: Check to see if a file is sorted.
 * This assumes that each record is a pair of short ints
 * with the first short being the key value
 * @author CS3114 Instructor and TAs
 * @version 10/18/2014
 */

import java.io.*;

public class CheckFile {
  public static void main(String args[]) throws IOException {

    if (args.length != 1) {
      System.out.println("Usage: CheckFile <name>");
      return;
    }
    DataInputStream in = new DataInputStream(new BufferedInputStream(new FileInputStream(args[0])));
    if ((in.available() < 4) || ((in.available() % 4) != 0)) {
      System.out.println("File size of " + in.available() + " bytes indicates a bad file");
      return;
    }
    // Prime with the first record
    short key2 = in.readShort();
    short value2 = in.readShort();
    int reccnt = 0;

    try {
      while (true) {
        short key1 = key2;
        short value1 = value2;
        key2 = in.readShort();
        value2 = in.readShort();
        reccnt++;
        if(key1 > key2) {
          System.out.println("Key " +  key1 + " at position " + (reccnt - 1) +
                             " is out of order with key " + key2 + " at position " + reccnt);
        }
      }
    } catch (EOFException e) {
      System.out.println(reccnt + " records processed");
    }
  }
}