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use std::collections::HashSet;
use std::io::{self, Read};
fn solve1(input: &str) -> u32 {
let mut banks: Vec<u32> = input.split_whitespace()
.map(str::parse)
.map(Result::unwrap)
.collect();
let mut states = HashSet::new();
for cycle in 0.. {
if !states.insert(banks.clone()) {
return cycle;
}
let (index, mut blocks) = banks.iter()
.cloned()
.enumerate()
.rev()
.max_by_key(|&(_, n)| n)
.unwrap();
banks[index] = 0;
for bank in (0..banks.len()).cycle().skip(index + 1) {
banks[bank] += 1;
blocks -= 1;
if blocks == 0 {
break;
}
}
}
unreachable!()
}
fn main() {
let mut input = String::new();
io::stdin().read_to_string(&mut input).unwrap();
println!("Part 1: {}", solve1(input.trim()));
}
#[test]
fn part1() {
assert_eq!(5, solve1("0 2 7 0"));
}
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