We toss coin to choose one from two. But Taheri has invented a new tossing method named Dhele Dei .You can choose one from many people with this method . In this method, he gives each person a tossing code and tosses a coin according to necessity . For example, if Hiron has a code like TTHHT , the tossing outcomes are T, T,H,H and T respectively and Taheri tosses the coin just 5 times, Hiron will be selected. Taheri always tosses the coin not more than his necessity. The tossing code is changeable to toss the coin fewest times.
If Taheri want to choose 3 people from 2050 people, how many times he have to toss a coin?
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When you flip a coin x amount of times, there will be 2 x unique solutions. This means that if you have 2 x people, you can flip a coin x amount of times. However, if you have more than 2 x people, you will need more than x coin flips.
In this case, there are 2 0 5 0 people. The closest power of 2 is 2 0 4 8 = 2 1 1 . If there were 2 0 4 8 or less people, we could only do it will 1 1 coin flips. However, because 2 0 5 0 is greater than 2 1 1 , we need 1 2 coin flips to determine the first person.
When we are determining the second person, we only have 2 0 4 9 people. It is still greater than 2 1 1 , so we still need 1 2 coin flips.
However, when choosing the third and final person, we only have 2 0 4 8 people, which is less than or equal to 2 1 1 . Because of this, we only need 1 1 coin flips to determine the third person.
Overall, we needed 1 2 + 1 2 + 1 1 = 3 5 coin flips.