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@ -1,20 +1,24 @@
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use std::collections::HashSet;
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use failure::*;
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#[allow(dead_code)]
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pub fn solve(input: &str) -> Result<String, Error> {
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let banks: Vec<_> = input
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.split_whitespace()
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.map(str::parse)
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.collect::<Result<_, _>>()?;
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let mut reallocation = Reallocation { banks: banks.clone() };
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let mut reallocation = Reallocation {
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banks: banks.clone(),
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};
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let cycles = unique_cycles(reallocation);
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reallocation = Reallocation { banks };
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Ok((unique_cycles(reallocation.skip(cycles - 1)) - 1).to_string())
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}
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fn unique_cycles<R: Iterator<Item=Vec<usize>>>(reallocation: R) -> usize {
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#[allow(dead_code)]
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fn unique_cycles<R: Iterator<Item = Vec<usize>>>(reallocation: R) -> usize {
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let mut seen = HashSet::new();
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for (i, banks) in reallocation.enumerate() {
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if seen.contains(&banks) {
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@ -28,10 +32,13 @@ fn unique_cycles<R: Iterator<Item=Vec<usize>>>(reallocation: R) -> usize {
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#[test]
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fn test_part_one() {
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let reallocation = Reallocation { banks: vec![0, 2, 7, 0] };
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let reallocation = Reallocation {
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banks: vec![0, 2, 7, 0],
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};
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assert_eq!(unique_cycles(reallocation), 5);
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}
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#[allow(dead_code)]
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struct Reallocation {
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banks: Vec<usize>,
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}
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