B'Dasha, an excellent student, is studying at the best mathematical lyceum in the country. Recently, a mysterious stranger brought n words consisting of small latin letters s_1, s_2, ldots, s_n to the lyceum. Since that day, Dasha has been tormented by nightmares. Consider some pair of integers langle i, j rangle ( 1 <= i <= j <= n ). A nightmare is a string for which it is true: For example, if s_i= "abcdefg" and s_j= "ijklmnopqrstuvwxyz", the pair langle i, j rangle creates a nightmare. Dasha will stop having nightmares if she counts their number. There are too many nightmares, so Dasha needs your help. Count the number of different nightmares. Nightmares are called different if the corresponding pairs langle i, j rangle are different. The pairs langle i_1, j_1 rangle and langle i_2, j_2 rangle are called different if i_1 neq i_2 or j_1 neq j_2 . The first line contains a single integer n ( 1 <= n <= 2 cdot 10^5 ) -- the number of words. The following n lines contain the words s_1, s_2, ldots, s_n , consisting of small latin letters. It is guaranteed that the total length of words does not exceed 5 cdot 10^6 . Print a single integer -- the number of different nightmares. In the first test, nightmares are created by pairs langle 1, 3 rangle , langle 2, 5 rangle , langle 3, 4 rangle , langle 6, 7 rangle , langle 9, 10 rangle . '...