Tree Similarity

You are given two labeled, ordered, rooted trees $T$ and $T'$ (each node holds a number). Write a program that computes the distance between $T$ and $T'$, defined as the minimum number of operations needed to make $T$ equal to $T'$.

There are three operations:

1. Change the number written on one node of $T$.
2. Delete one non-root node of $T$.
3. Insert one node somewhere below the root of $T$.

Because $T$ and $T'$ are ordered trees, if a non-leaf node has $c$ children, those children are ordered from the 1st to the $c$-th.

Two trees $X$ and $Y$ are equal if their roots hold the same number and have the same number of children, and, for every $i$, the subtree rooted at the $i$-th child of $X$ is equal to the subtree rooted at the $i$-th child of $Y$ ($i = 1, 2, \dots, c$).

Deletion and insertion are defined as follows. Suppose a non-root node $w$ has $d$ children, its parent is $u$, and $w$ is the $i$-th child of $u$. When $w$ is deleted, its children move up into $w$'s place: the first child of $w$ becomes the $i$-th child of $u$, the second becomes the $(i+1)$-th child of $u$, and so on. The children of $u$ at positions $j < i$ keep their order, while every child at position $j > i$ is shifted to become the $(j + d - 1)$-th child of $u$.

To insert a non-root node $w$, first choose the node $u$ that will become its parent. Then pick a contiguous subsequence of $u$'s children, make them the children of $w$, and place $w$ in their position. When inserting $w$, you may write any number on it.

You may not delete the root of $T$ or insert a new node above the root. However, you may change the number written on the root.

(For example, one may delete a node $w$, or take the 2nd through 4th children of $u$, group them as the children of a new node $w$, and insert $w$ below $u$.)

The first line contains the node counts $n$ and $m$ of the two trees $T$ and $T'$ ($1 \le n, m \le 60$).

The next $n$ lines describe $T$. Nodes are numbered from $0$ to $n-1$; the $(i+1)$-th of these lines describes node $i$. Each line gives the number written on that node and its number of children, followed by the indices of its children in order (indices are 0-based).

The following $m$ lines describe $T'$ in the same format.

Every number written on a node is a non-negative integer, and the root of each tree is the node that is not a child of any other node.

Print the minimum number of operations needed to make $T$ equal to $T'$.