Trigger functionality for child to parent updation

Trigger Contacttrigger on Contact(after  update){

    set<String> setcon=new set<String>();

    for(Contact c:Trigger.new){

       setcon.add(c.Email);

    }

List<Account> acclist=[select Id,Name,Email__c,(select Id,Name,Email from Contacts) from Account  where Email__c in:setcon];

    Map<id,Account> mapacc=new  Map<id,Account>();

    for(Account acc:accList){

        mapacc.put(acc.Id,acc);

        System.debug(mapacc);

        System.debug('Record data is'+mapacc);

      

        if(mapacc.containsKey(acc.Id)){

           acc.Email__c='default@gmail.com';

          

        }

                  

        }

    update accList;

}