Given cards numbered from 1 to 9 placed face up and two dice, you repeatedly throw the dice. If the sum is greater than 9, you throw again. If the sum is less than or equal to 9, you have two options: flip down the card with the number equal to the sum, or flip down the two cards corresponding to each die value. For example, if you roll a 3 and a 4, you can flip down the 7, or both the 3 and 4. If the card for the sum is already flipped, you must flip down each die's card if possible; if one of those is already flipped, you must flip the sum (if possible). The game ends when no move is possible, and your score is the number of flipped cards. What is the best strategy?