38 lines
900 B
Rust
38 lines
900 B
Rust
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use std::time::{Duration, Instant};
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const END: usize = 30_000_000;
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pub fn run(print: bool) -> Duration {
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let input: Vec<usize> = "0,1,5,10,3,12,19"
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.split(",")
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.map(|i| i.parse().unwrap())
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.collect();
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let instant = Instant::now();
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let mut history = vec![0; END];
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let mut last = input[0];
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for turn in 0..input.len() {
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history[last] = turn;
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last = input[turn];
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}
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for turn in input.len()..2020 {
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let stored = history[last];
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history[last] = turn;
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last = if stored == 0 { 0 } else { turn - stored };
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}
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if print {
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println!("Part 1: {}", last);
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}
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for turn in 2020..END {
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let stored = history[last];
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history[last] = turn;
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last = if stored == 0 { 0 } else { turn - stored };
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}
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if print {
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println!("Part 2: {}", last);
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}
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instant.elapsed()
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}
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