Dateri is a well known aquaman and he has n girl friends. Each girl's name contains only lowercase letters and the \(i_{th}\) girl's name is \(s_i\). Girls will break up with Dateri if he incorrectly spells the prefix and suffix of her name when they are dating. Dateri is greedy and he don't want to lose any girlfriend. So he wants to remember a longest common prefix and a longest common suffix of their names. Please find the product of the length of the longest common prefix and the length of the longest common suffix of these strings.