var i = 3;

	function ShowInfo( city, city_num ) {
	   if( i!=0 ) {
		   var act_info = document.getElementById( 'info' + i );
			 act_info.className = 'pr-descr-none';
       act_info.id = 'info' + i;
			 
			 var act_city = document.getElementById( 'town' + i );
			 act_city.className = '';
			 act_city.id = 'town' + i; 
		 }
		 
		 i = city_num; 
		 
		 var info_id = 'info' + city_num;
	   var info = document.getElementById( info_id );
		 info.className = 'pr-descr'; 
		 city.className = 'red';
		 
	 }