++i Vs i++

          Readers from a C background might be surprised that we use the prefix increment in the programs we've written. The reason is simple: The prefix version does less work. It increments the value and returns the incremented version. The postfix operator must store the original value so that it can return the unincremented value as its result. For ints and pointers, the compiler can optimize away this extra work. For more complex iterator types, this extra work potentially could be more costly. By habitually favoring the use of the prefix versions, we do not have to worry if the performance difference matters.