# Old pals

Some pals from the good old days at the university plan to meet again
and have a party. To decide how the party will be, they have written a
list of categories (for food, music, etc), each one with several
possibilities. All the categories are mutually independent, that is,
what is chosen for a category does not affect what can be chosen for
another one.

Consider the first example in the sample input. Depending on the cooker,
they can have as main dish either fast food or vegetarian food.
Depending on who chooses the music, it can be classic, alternative or
heavy. One of the friends has two specialties: making milk shakes and
baking croissants, but he has only time for one of them. Finally, they
can even enjoy a sauna or a swimming pool, depending on whose house the
party takes place.

![image](foto.jpg){width="5.5cm"}

They are too fastidious, but they finally agree to require two
conditions, and to go to the party if at least one of them is satisfied.
Following the example, Mr. Morito likes milk shakes and saunas,
Mr. Vinyes prefers alternative music and croissants, Mr. Masdeu likes
heavy music and vegetarian food, while Mr. Maltines enjoys fast food and
saunas. One possible solution is eating vegetarian food and croissants
in a house with sauna, listening to any kind of music (or to no music at
all).

Let us formalize the problem. There is a list of categories and a list
of friends. Every category has several possibilities. Every friend asks
for two different conditions chosen among the possibilities of the
categories. Your task is to decide if there is a way to pick (at most)
one possibility per category so that at least one condition per friend
is satisfied.

## Input

Input begins with the number of cases. Every case has two parts: the
first for the categories, the second for the conditions. The categories'
part begins with a number $c \ge 1$ followed by $c$ lines, each one with
at least two possibilities (strings). The conditions' part begins with a
number $1 \le f \le 1000$ followed by $f$ lines, each one with three
strings: the surname's friend and two different conditions present in
the categories part.

Every string has at most 20 letters and underscores. The strings in the
categories' part of the same case are all different. For each case, the
total number of possibilities of all the categories is at most 200.

## Output

For every case, print the case number, followed by the right answer
"`yes`" or "`no`".

## Problem information

Author: Salvador Roura

Generation: 2026-01-25T12:03:12.877Z

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