Your task is to divide a number of persons into two teams, in such a way, that: everyone belongs to one of the teams; every team has at least one member; every person in the team knows every other person in his team; teams are as close in their sizes as possible. This task may have many solutions. You are to find and output any solution, or to report that solution does not exist.
Your task is to divide a number of persons into two teams, in such a way, that: everyone belongs to one of the teams; every team has at least one member; every person in the team knows every other person in his team; teams are as close in their sizes as possible. This task may have many solutions. You are to find and output any solution, or to report that solution does not exist.
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