33 lines
721 B
Plaintext
33 lines
721 B
Plaintext
use itertools::Itertools;
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fn solve(deck: &[usize]) -> usize {
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let mut counter = 0_usize;
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let mut shuffle = deck.to_vec();
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loop {
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let p0 = shuffle[0];
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if p0 == 1 {
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break;
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}
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shuffle[..p0].reverse();
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counter += 1;
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}
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counter
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}
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// this is a naive method which tries all permutations and works up to ~12 cards
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fn topswops(number: usize) -> usize {
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(1..=number)
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.permutations(number)
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.fold(0_usize, |mut acc, p| {
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let steps = solve(&p);
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if steps > acc {
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acc = steps;
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}
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acc
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})
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}
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fn main() {
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(1_usize..=10).for_each(|x| println!("{}: {}", x, topswops(x)));
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}
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