Hi 
    I am trying hard to write test class for the below

trigger Activitytri on Task(after update) 
{
Set<String> accids = new Set<String>();


    Set<String> phoneStrSet = new Set<String>();
    string taskacno ;
    for(task acc: Trigger.new) 
    {
    taskacno = acc.accountid;
                  accids .add(acc.Account_Ph_No__c);
         List<Task> accListS = [select accountid from task where accountid  IN :accids  AND CallDisposition LIKE '%Lead%'];
            if(accListS != null && !accListS .isEmpty()) 
            {
             phoneStrSet.add(acc.Account_Ph_No__c);

            }
     

            }

    

   
    if(!phoneStrSet.isEmpty()) 
    {
        List<Account> accList = [Select Id,IsPersonAccount,StrPhr_Do_Not_Call_Group_Practice__c, PersonDoNotCall,StrPhr_Lead_Qualified__c  from Account where Phone IN: phoneStrSet ];        {
            for(Account acc: accList) 
            {
               if ( acc.IsPersonAccount == true && acc.StrPhr_Do_Not_Call_Group_Practice__c == False && acc.ID ==taskacno )  
            
                {
                acc.StrPhr_Do_Not_Call_Group_Practice__c=True;
                 //acc.PersonDoNotCall = True;

                                   }
                if ( acc.IsPersonAccount == true && acc.StrPhr_Do_Not_Call_Group_Practice__c == False && acc.ID !=taskacno ) 
                {
                acc.StrPhr_Do_Not_Call_Group_Practice__c=True;
                 acc.PersonDoNotCall = True;

                                   }

                                   
                         }
            update accList;
        }
    }
}