public String encode(String plain)
	 {
		 Morse_code m=new Morse_code();
		 
		 String plain_u=plain.toUpperCase();
		 StringBuilder sb=new StringBuilder();
		 for (char c: plain_u.toCharArray())
		 {
			 if(c!=' ')
			 {
			   sb.append(m.get_morse_code(c));
			   sb.append("x");
			 }
			 else
			 {
				 sb.append("x");
			 }
		 }
		 sb.append("x");
		 String mc=sb.toString();
		 int tri=mc.length()/3;
		 int tri_near=tri*3;
		 if(tri_near<mc.length())
		 {
			 mc=mc.substring(0,tri_near);
		 }
		 StringBuilder cb=new StringBuilder();
		 for(int i=0;i<mc.length();i+=3)
		 {
			 String cur_m=mc.substring(i,i+3);
			 cb.append(h_map.get(cur_m));
		 }
		 return cb.toString();
	 }