CCITT4.java

public class Gp4 {
  public static void main(String... args ){
    java.util.Scanner read = new java.util.Scanner(System.in);
    System.out.println("Number of Lines are: ");
    int no = read.nextInt();
    
    String[] input = new String[no];
    
    for(int i=0; i<no ; ){
   //   System.out.println("Enter for i = "+i);
      input[i] = read.next();
      i = i+1;
    }
    
    int k = 3;
     
    processInput(input, k);
  }
  
  private static void processInput(String[] ip, int k){
    String[] temp = null; 
    
    for(int i=0 ; i<ip.length ; ++i){
      if(i%k == 0){
        temp  = new String[k];        
      }
      temp[i%k] = ip[i]; 
      if(i%k == k-1)
        processBlock(temp);
    }
  }
  
  private static void processBlock(String[] block){
     if(block == null || block.length == 0)
       return;
       
     String line1 = block[0];
     System.out.println("Block Encoding Started");
  //   System.out.println(block[0]);
     for(int i=1; i<block.length ; ++i){
       processLines(block[i-1], block[i]);
     }
     System.out.println("Block Encoding Ends");
  }
  
  private static void processLines(String ref, String line){            
  //  System.out.println("Ref is: "+ref+"\n Line is: "+line);
    
    String temp="";
       for(int i=0 ; i<ref.length() ; ++i){
         if(ref.charAt(i) == line.charAt(i))
              temp = temp + "0";
         else
              temp = temp + "1";
      }

       char current = temp.charAt(0);
       int count = 0;
       
       for(int i=0 ; i<temp.length() ; ++i){
           if(temp.charAt(i) == current)
             ++count;
           else{
             System.out.print(" "+current + " " + count);
             current = temp.charAt(i);
             count = 1;
         }
      }
      System.out.println();
  }
}