Binary strings

A binary string is a sequence composed solely of the characters '0' and '1'. A suffix of a string is formed by removing the first K (where K ≥ 0) characters from the original string. For instance, the suffixes of the string "1001" are "1001", "001", "01", "1", and the empty string.

You are provided with N binary strings. Your task is to determine how many pairs of these strings have one string as a suffix of the other.

Input

The first line contains an integer N (2 ≤ N ≤ 100000). Each of the following N lines contains one non-empty binary string. The total length of all strings combined does not exceed 200000.

Output

Output a single integer representing the number of such pairs.

Examples