Difference between revisions of "KGS math club/solution 11 2"

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Given n, k, and a a k-member subset K of the n-member set N, we form the (n-k)-member subset it is paired with as follows.
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Given n, k, and a k-member subset K of the n-member set N, we form the (n-k)-member subset it is paired with as follows.
  
Assign integers modulo n to the members of N. Sort its members using these. Remove from N a member of K with a non-member of K that immediately follows it; and repeat until there are no members of K left. Append what we have left to K.
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Assign integers modulo n to the members of N, and cyclically order its members using them. Remove from N a member of K with a non-member of K that immediately follows it; and repeat until there are no members of K left. Append what we have left to K.

Revision as of 08:34, 14 February 2011

Given n, k, and a k-member subset K of the n-member set N, we form the (n-k)-member subset it is paired with as follows.

Assign integers modulo n to the members of N, and cyclically order its members using them. Remove from N a member of K with a non-member of K that immediately follows it; and repeat until there are no members of K left. Append what we have left to K.