import java.io.*;
class akik
{
	public static void main(String s[])
	{
		try
		{
			BufferedReader bfr=new BufferedReader(new InputStreamReader(System.in));
			System.out.println("Enter the path of the Source directory");
			String n1=bfr.readLine();
			File sour = new File(n1);
			System.out.println("Enter the path of the modified directory");
			String n2=bfr.readLine();
			File mod = new File(n2);
			System.out.println("Enter the path of the saved directory");
			String n3=bfr.readLine();
			File save = new File(n3);
			(new File(n3+"/unique")).mkdir();
			File saveu = new File(n3+"/unique");
			String[] chils = sour.list();
			if (chils == null) {
  				System.out.println("Invalid Directory");
			}
			String[] chilm =mod.list();
			if (chilm == null) {
  				System.out.println("Invalid Directory");
			}
			for(int i=0;i<chilm.length;i++)
			{
				Boolean ff=false;
				for(int j=0;j<chils.length&&!ff;j++)
				{

					if(chilm[i].equals(chils[j])&&((new File(n2,chilm[i])).isDirectory())&&(new File(n1,chils[j]).isDirectory()))
					{

						check(n2+"/"+chilm[i],n1+"/"+chils[j],n3);
						ff=true;

					}
					else if(chilm[i].equals(chils[j]))
					{
						ff=true;
						if(!compare(n2+"/"+chilm[i],n1+"/"+chils[j]))
						{
							System.out.println();
							copy(new File(n2+"/"+chilm[i]),new File(save,chilm[i]));


						}

					}
				}
				if(!ff)
				{
					copy(new File(n2+"/"+chilm[i]),new File(saveu,chilm[i]));
				}
			}

		}
		catch(Exception e)
		{
			System.out.println(e);
		}
		System.out.println("FILE COPY PROGRAM DONE");
	}
	static void  check(String a,String b,String c)
	{
		try
		{

		File f1=new File(a);
		File f2=new File(b);
		File save=new File(c);
		File saveu=new File(c+"/unique");
		String[] s1=f1.list();
		String[] s2=f2.list();

		for(int i=0;i<s1.length;i++)
		{

			Boolean ff=false;
			for(int j=0;j<s2.length&&!ff;j++)
			{

				if(s1[i].equals(s2[j]))
				{

					if((new File(a,s1[i]).isDirectory())&&(new File(b,s2[j]).isDirectory()))
					{

						check(a+"/"+s1[i],b+"/"+s2[j],c);
						ff=true;
					}
					else if(!compare(a+"/"+s1[i],b+"/"+s2[j]))
					{
						copy(new File(f1,s1[i]),new File(c,s1[i]));
						ff=true;
					}

				}

			}
			if(!ff)
			{
				copy(new File(f1,s1[i]),new File(c+"/unique",s1[i]));
			}
		}
		}
		catch(Exception e)
		{
		System.out.println(e+"akik");
		}

	}
	static Boolean compare(String filePath1,String filePath2){
	try{
	File f1 = new File(filePath1);
	File f2 = new File(filePath2);
	if(f1.length() == f2.length()){
	FileInputStream fis1 = new FileInputStream(f1);
	FileInputStream fis2 = new FileInputStream(f2);

	while(true){
	int a = fis1.read();
	int b = fis2.read();
	if(a != b){
	return false;
	}
	if(a == -1){
	return true;
	}
	}
	}else{
	return false;
	}

	}catch(Exception e){
	e.printStackTrace();
	}
	return false;
	}
	static void copy(File src, File dst) throws IOException {
    	InputStream in = new FileInputStream(src);
    	OutputStream out = new FileOutputStream(dst);

    	byte[] buf = new byte[1024];
    	int len;
    	while ((len = in.read(buf)) > 0) {
        out.write(buf, 0, len);
    	}
    	in.close();
    	out.close();
	}

}