A948.Guess the Animal--Bronze

普及-

USACO

通过率:0%

时间限制:1.00s

内存限制:128MB

题目描述

When bored of playing their usual shell game, Bessie the cow and her friend
Elsie like to play another common game called "guess the animal".
Initially, Bessie thinks of some animal (most of the time, this animal is a
cow, making the game rather boring, but occasionally Bessie is creative and
thinks of something else). Then Elsie proceeds to ask a series of questions to
figure out what animal Bessie has selected. Each question asks whether the
animal has some specific characteristic, and Bessie answers each question with
"yes" or "no". For example:
Elsie: "Does the animal fly?"
Bessie: "No"
Elsie: "Does the animal eat grass?"
Bessie: "Yes"
Elsie: "Does the animal make milk?"
Bessie: "Yes"
Elsie: "Does the animal go moo?"
Bessie: "Yes"
Elsie: "In that case I think the animal is a cow."
Bessie: "Correct!"
If we call the "feasible set" the set of all animals with characteristics
consistent with Elsie's questions so far, then Elsie keeps asking questions
until the feasible set contains only one animal, after which she announces
this animal as her answer. In each question, Elsie picks a characteristic of
some animal in the feasible set to ask about (even if this characteristic
might not help her narrow down the feasible set any further). She never asks
about the same characteristic twice.
Given all of the animals that Bessie and Elsie know as well as their
characteristics, please determine the maximum number of "yes" answers Elsie
could possibly receive before she knows the right animal.

输入格式

The first line of input contains the number of animals, NN (2N1002 \leq N \leq 100). Each of the next NN lines describes an animal. The line starts with
the animal name, then an integer KK (1K1001 \leq K \leq 100), then KK
characteristics of that animal. Animal names and characteristics are strings
of up to 20 lowercase characters (a..z). No two animals have exactly the same
characteristics.

输出格式

Please output the maximum number of "yes" answers Elsie could receive before
the game ends.

输入输出样例

  • 输入#1

    4
    bird 2 flies eatsworms
    cow 4 eatsgrass isawesome makesmilk goesmoo
    sheep 1 eatsgrass
    goat 2 makesmilk eatsgrass
    

    输出#1

    3
    

说明/提示

In this example, it is possible for Elsie to generate a transcript with 3
"yes" answers (the one above), and it is not possible to generate a transcript
with more than 3 "yes" answers.

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