Hi Developer,

I have written a sample piece of code .Here it is 

Public class TotalPrice_cls{
public static void calTotal(Book__c[] b)
{
for(Book__c[] s: b)
s.Total_Price__c = s.Price__c* s.Quantity__c;

}
}
While running the code it displays the error message as :Error: Initial term of field expression must be a concrete SObject: LIST<Book__c> at line 9 column 1.
May i know the reason for this error message. Thanks in advance.