8. In front of a holy temple by the Indus River, a brass plate stands with 3 golden needles, on which many golden discs are threaded. It is said that at the time of creation by Brahma, 64 golden discs of varying sizes were placed on the leftmost needle, and he required people to move all 64 discs to the rightmost needle according to the rule "only one disc can be moved at a time, and a smaller disc must always be on top of a larger disc." He predicted that when all 64 discs are moved from the left needle to the right, the universe would be annihilated.
Now, there are only 6 golden discs on the leftmost needle (A), as shown in Figure (1). To move them according to the rules to the state shown in Figure (2), at least _ steps are needed.
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