How to pass an array of strings to an SQL Server stored procedure

My stored procedure:-

USE [hrms]
GO
/****** Object: StoredProcedure [dbo].[sp_load_resumes] Script Date: 8/23/2013 10:59:11 PM ******/
SET ANSI_NULLS ON
GO
SET QUOTED_IDENTIFIER ON
GO



-- =============================================
-- Author: Roshan George V
-- =============================================


ALTER procedure [dbo].[sp_load_resumes]
@flag int=0,
@skill_name varchar(max)=null
as
if(@flag=0)
begin
select skill_name from tbl_skills where skill_name IN (' + @skill_name + ')
end
go


My c# code:-

string Doc_Content = doc.Content.Text;
string str = Doc_Content;
var words = str.Split(new char[] { ' ', ':', '\r', '\t' });
//var words = str.Split(new char[] { ':', '\r', '\t' });

SqlCommand cmd3 = new SqlCommand("sp_load_resumes", obj.con);
cmd3.CommandType = CommandType.StoredProcedure;
cmd3.Parameters.Add("@flag", 2);

//Loop with the foreach keyword.
/*foreach (var value in words)
{
cmd3.Parameters.Add("@skill_name", value);
}*/
for (int i = 0; i < words.Length; i++)
{
skill_words = string.Join(",", words[i].ToString());

}
//skill_words=string.Join(",",
cmd3.Parameters.Add("@skill_name", skill_words);
cmd3.ExecuteNonQuery();

//string t_return = cmd3.Parameters["@temp_skill_name"].Value.ToString();




DataTable dt = new DataTable();
SqlDataAdapter adt = new SqlDataAdapter(cmd3);
adt.Fill(dt);

ArrayList arr = new ArrayList();
foreach (DataRow row in dt.Rows)
{
arr.Add(row.ToString());
}
Label9.Text = arr[1].ToString();
Label8.Text = arr[2].ToString();
Label10.Text = arr[3].ToString();
Label11.Text = arr[4].ToString();

Can you provide a sample?