# How many minimum number of questions you need to ask to know the celebrity name?

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There are (n+1) people in a party, they might or might not know each others names.

There is one celebrity in the group(total n +1 people), celebrity does not know any of n peoples by name and all n people know celebrity by name.

You are given the list of people's names(n+1), You can ask only one question from the people. DO YOU KNOW THIS NAME ?

HOW MANY MINIMUM NUMBER OF QUESTIONS YOU NEED TO ASK TO KNOW THE CELEBRITY NAME?

NOTE: assume all names are unique.

posted Oct 27, 2014

+1 vote

Let’s say you ask from A that Do you know B?
If A knows B => A can not be a celebrity.
If A does not know B then B can not be a celebrity.

So you strike out one name from your list, so on each question you can reject one name, thus you need to ask a maximum of (n) questions to correctly figure out celebrity name.

it should be n questions not (n+1) according to your logic
Yes you are right should be n making a correction.

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