Natalie is a famous jewellery designer, known for her pearl necklace designs. She has a team that helps her create unique designs made of different types of pearls. The team creates individual string of pearls, and Natalie then arranges the strings in a beautiful way to make necklace. To begin with, Natalie prepares a rough sketch of the necklace by using a single character code to represent every pearl type she uses. The necklace design therefore looks like a series of strings in N different lines. Natalie's secret to making beautiful design to follow one specific rule. The rule is that two pearl strings can be consecutively arranged only if the two strings have a similar suffix chain such that length of the similar suffix chain is atmost one less than the length of the longer string i.e. two strings A and B are consecutively arranged only if LSC(A,B) >= max(|A|,|B|)-1 , where |A| indicates the length of string A.