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Niebieskie ksi.eczki
IV Olimpiada Informatyczna 1996/1997

Task: LIC
Author: Wojciech Rytter
The number of symmetrical choices

I stage contest  
Source fileLIC.??? (e.g. PAS,C, CPP)
Executable fileLIC.EXE
Input fileLIC.IN
Output fileLIC.OUT

We are given two sequences of words: (x1,...,xn) and (y1,...,yn), 1 <= n <= 30. For every i, 1<=i<=n, we chose one of the two words: xi or yi. The chosen words are merged in order of increasing indices. The choice consists of n steps. In each step we decide to take the i-th word from the first or from the second sequence of words. More formally: the choice is a sequence of length n whose elements are numbers 1 and 2. It is possible that different choices lead to the same word. We say that a choice is symmetrical if its result is a palindrome, i.e. a word that is identical when we read it from left to right and from right to left.

Task

Write a program that:

  • reads from the text file LIC.IN: the number n and two sequences of words (x1,...,xn) and (y1,...,yn),
  • computes the number of symmetrical choices for the given sequences,
  • writes the result to the text file LIC.OUT.

Input

In the first line of the text file LIC.IN there is one positive integer n <= 30. In the following n lines there are written consecutive words of the sequence (xi) - one word in one line. In the following n lines there are written (in the similar way) consecutive words of the sequence (yi). Each word consists solely of small letters of the English alphabet (from a to z) and its length is from the range [1..400].

Output

In the text file LIC.OUT there should be written one non-negative integer - the number of symmetrical choices.

Example

For the file LIC.IN

5
ab
a
a
ab
a
a
baaaa
a
a
ba
the correct answer is the text file LIC.OUT:
12





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