There is a group of 30 people who communicate only by phone. During any one to one phone conversation the two members exchange all their information. Find the number of calls needed so that everyone finds out every bit of news.

Thanks for any help you can give me!!

2. number of calls = c(30,2) = 30.29

3. Originally Posted by peaz9482
There is a group of 30 people who communicate only by phone. During any one to one phone conversation the two members exchange all their information. Find the number of calls needed so that everyone finds out every bit of news.

Thanks for any help you can give me!!
Interesting.

I recommend starting with smaller networks first to try to get a handle. For example, with four people, you can think of four binary numbers between 0000 and 1111 representing the state of each person's knowledge, and the following scenario can happen

Code:
0001   0010   0100   1000
0011   0011   0100   1000
0011   0011   1100   1100
0011   1111   1111   1100
1111   1111   1111   1111
I don't know the solution to your problem, but already the above example provides a feel for what an optimal calling sequence (algorithm) might be.