21. The method according to claim 12 , wherein the count code comprises at least a third count word in addition to the less significant and more significant words, and wherein making the first assignment comprises assigning a third group of the memory cells to store the third count word, and wherein making the second assignment comprises swapping the less significant word, the more significant word, and the third count word among the groups of the memory cells.
21. The method according to claim 12 , wherein the count code comprises at least a third count word in addition to the less significant and more significant words, and wherein making the first assignment comprises assigning a third group of the memory cells to store the third count word, and wherein making the second assignment comprises swapping the less significant word, the more significant word, and the third count word among the groups of the memory cells. 22. The method according to claim 21 , wherein the third count word has a level of significance that is intermediate between the more and less significant words.