nove.dev
:)
deduping
+13
-28
src/day3.rs
+13
-28
src/day3.rs
···
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1
pub fn day3_part1(input: &str) -> String {
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2
let batteries = parse(input);
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-
let sum: u64 = batteries.iter().map(|bank| max_joltage(bank)).sum();
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let sum: u64 = batteries.iter().map(|bank| max_joltage(bank, 2)).sum();
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sum.to_string()
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}
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pub fn day3_part2(input: &str) -> String {
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let batteries = parse(input);
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let sum: u64 = batteries.iter().map(|bank| max_12_joltage(bank)).sum();
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let sum: u64 = batteries.iter().map(|bank| max_joltage(bank, 12)).sum();
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sum.to_string()
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}
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-
fn max_12_joltage(bank: &[u64]) -> u64 {
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+
fn max_joltage(bank: &[u8], battery_count: usize) -> u64 {
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let bank_length = bank.len();
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let mut digits = Vec::with_capacity(12);
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let mut digits = Vec::with_capacity(battery_count);
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let mut cursor = 0;
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for place in 0..12 {
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let max_digit = bank[cursor..bank_length - (12 - (place + 1))]
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.iter()
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.max()
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.unwrap();
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let index_of_max_digit = bank[cursor..bank_length - (12 - (place + 1))]
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for place in 0..battery_count {
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let range = cursor..bank_length - (battery_count - (place + 1));
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let (index_of_max_digit, max_digit) = bank[range]
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.iter()
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.enumerate()
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.find(|(_, digit)| *digit == max_digit)
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.unwrap()
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.0;
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.max_by_key(|(index, digit)| (*digit, bank_length - index))
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.unwrap();
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cursor = index_of_max_digit + cursor + 1;
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digits.push(max_digit)
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}
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digits.into_iter().fold(0, |acc, digit| acc * 10 + digit)
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}
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-
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fn max_joltage(bank: &[u64]) -> u64 {
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let bank_length = bank.len();
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let max_digit_not_final = bank[..bank_length - 1].iter().max().unwrap();
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let index_of_max_digit = bank
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digits
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.iter()
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.enumerate()
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.find(|(_, digit)| *digit == max_digit_not_final)
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.unwrap()
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.0;
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let max_ones = bank[index_of_max_digit + 1..].iter().max().unwrap();
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*max_digit_not_final * 10 + max_ones
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.fold(0, |acc, &&digit| acc * 10 + digit as u64)
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}
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fn parse(input: &str) -> Vec<Vec<u64>> {
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fn parse(input: &str) -> Vec<Vec<u8>> {
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input
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.lines()
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.map(|bank| {
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bank.chars()
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.map(|c| c.to_digit(10).unwrap() as u64)
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.map(|c| c.to_digit(10).unwrap() as u8)
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.collect()
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})
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.collect()