Whenever an account owner changed then the realted contacts owner also should be chnaged to Account owner and vice versa

Try the Following Code Just Copy Paste It.

trigger ownerUpdate on Contact (before Update) {
	Set<Id> relatedAccountId = new Set<Id>();
	List<Account> updatedList = new List<Account>();
    string ownerid;
    for(Contact con: trigger.new){
     if(con.AccountId != Null){
       relatedAccountId.add(con.AccountId);
       ownerid = con.OwnerId;
     }
   }
    for(Account acc: [Select Id, Name ,OwnerId from Account where id in : relatedAccountId]){
    acc.OwnerId = ownerid;
	updatedList.add(acc);
	}
	update updatedList;
}

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