public  class  Queen_problem
{
      public  static  void   main(String  args[])
      {      
         int i,letter=0,digit=0,space=0,others=0; 
         char c[];
         String str=new String("My address is #168 Shanghai Road,Beijing,100028.");         
         c=new char[str.length()];         
         str.getChars(0,str.length(),c,0);                
         
         for  (i=0;i<c.length;i++)
            if((c[i]>='a'&&c[i]<='z')||(c[i]>='A'&&c[i]<='Z')){
                 letter++;}
            else if (c[i]>='0'&&c[i]<='9'){
                 digit++;}
            else if (c[i]==' '){
                 space++;}
            else {
                 others++;}                     
          System.out.print("letter="+letter+";digit="+digit+
               ";space="+space+";others="+others);
          System.out.println();
      }
}