Genome Evolution

Xi is a developmental biologist who studies developmental distances between chromosomes. In Xi's simplified view a chromosome is a permutation of $n$ genes numbered $1$ to $n$. Xi is building a measure of evolutionary distance between two chromosomes. In Xi's theory of evolution, any set of genes that lies together in both chromosomes is a positive witness that the two chromosomes are similar.

A positive witness is a pair of sequences $A$ and $A'$ of the same length, where $A$ is a consecutive subsequence of the first chromosome, $A'$ is a consecutive subsequence of the second chromosome, and $A$ is a permutation of $A'$. Each chromosome contains every gene exactly once, so once $A$ is fixed there is at most one matching $A'$. Count the positive witnesses of the two given chromosomes whose length is greater than one.

The input contains several test cases. Each test case starts with a line containing the number of genes $n$ ($2 \le n \le 3000$). The next two lines contain the two chromosomes, one per line, each as a list of positive integers that uses every number from $1$ to $n$ exactly once. A line containing a single $0$ ends the input and is not a test case.

For each test case, print one line with the number of positive witnesses for the two chromosomes.