nove.dev
:)
day3 part2
+32
-5
src/day3.rs
+32
-5
src/day3.rs
···
1
1
pub fn day3_part1(input: &str) -> String {
2
2
let batteries = parse(input);
3
-
let sum: u32 = batteries.iter().map(|bank| max_joltage(bank)).sum();
3
+
let sum: u64 = batteries.iter().map(|bank| max_joltage(bank)).sum();
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sum.to_string()
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5
}
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pub fn day3_part2(input: &str) -> String {
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let batteries = parse(input);
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todo!()
8
+
let sum: u64 = batteries.iter().map(|bank| max_12_joltage(bank)).sum();
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sum.to_string()
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}
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+
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fn max_12_joltage(bank: &[u64]) -> 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 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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.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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cursor = index_of_max_digit + cursor + 1;
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digits.push(max_digit)
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}
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+
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digits.into_iter().fold(0, |acc, digit| acc * 10 + digit)
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}
10
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11
-
fn max_joltage(bank: &[u32]) -> u32 {
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+
fn max_joltage(bank: &[u64]) -> u64 {
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35
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
···
21
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*max_digit_not_final * 10 + max_ones
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}
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-
fn parse(input: &str) -> Vec<Vec<u32>> {
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+
fn parse(input: &str) -> Vec<Vec<u64>> {
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input
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.lines()
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-
.map(|bank| bank.chars().map(|c| c.to_digit(10).unwrap()).collect())
50
+
.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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.collect()
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+
})
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.collect()
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}
+7
-7
src/lib.rs
+7
-7
src/lib.rs
···
128
128
let result = day3::day3_part1(include_str!("../input/day3.txt"));
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assert_eq!(result, "17613");
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}
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-
// #[test]
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// fn day3_part2_test() {
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// let test_result = day3::day3_part2(include_str!("../input/day3.test.txt"));
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// assert_eq!(test_result, "4174379265");
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// let result = day3::day3_part2(include_str!("../input/day3.txt"));
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// assert_eq!(result, "45283684555");
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// }
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#[test]
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fn day3_part2_test() {
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let test_result = day3::day3_part2(include_str!("../input/day3.test.txt"));
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assert_eq!(test_result, "3121910778619");
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+
let result = day3::day3_part2(include_str!("../input/day3.txt"));
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assert_eq!(result, "175304218462560");
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+
}
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#[test]
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fn day2_part1_test() {