The game involves four people driving on six separate days. Each person must drive on at least one of the days. These rules tell us that when we determine how many days each person drives, at least one person and at most two people could drive more than one day. In a scenario where only one person out of four drives on more than one day, this person has to drive on 3 out of 6 days, and the rest of the people each drive 1 day, resulting in 3-1-1-1 days per/ person. In a scenario where two people drive for more than one day, two people each drive on two of the days, and the rest drive on one day, resulting in 2-2-1-1 days per/ person.
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