How to add script in SharePoint web part

Add the script in webpart.cs file.     

 private const string EmbeddedScriptFormat = "<script language=\"javascript\">$(document).ready( function(){alert('hi');});</script>";

        //TESTWEBPART() is the default constructor name of the webpart class

        public TESTWEBPART()
        {
            this.PreRender += new EventHandler(WebPart_ClientScript_PreRender);
        }

        private void WebPart_ClientScript_PreRender(object sender, System.EventArgs e)
        {
            if (!Page.IsClientScriptBlockRegistered(ByeByeIncludeScriptKey))
                Page.RegisterClientScriptBlock(ByeByeIncludeScriptKey,
                EmbeddedScriptFormat);

        }