commit 8e4c8f548483d3c1ca640c0b358ba29e164b1074 · aylac.top/advent_of_code

2025/2/rust/Cargo.lock

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       # This file is automatically @generated by Cargo.

     

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       # It is not intended for manual editing.

     

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       version = 4

     

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       [[package]]

     

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       name = "rust"

     

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       version = "0.1.0"

2025/2/rust/Cargo.toml

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       [package]

     

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       name = "rust"

     

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       version = "0.1.0"

     

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       edition = "2024"

     

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       [dependencies]

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2025/2/rust/src/main.rs

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       struct Range {

     

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           start: u64,

     

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           end: u64,

     

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       }

     

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       fn main() {

     

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           let input: Vec<Range> = std::fs::read_to_string("../input.txt")

     

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               .expect("invalid input!!")

     

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               .trim()

     

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               .split(",")

     

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               .map(|v| {

     

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                   let range: Vec<&str> = v.split("-").collect();

     

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                   match range[..] {

     

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                       [start, end] => Range {

     

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                           start: start.parse().expect("invalid number"),

     

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                           end: end.parse().expect("invalid number"),

     

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                       },

     

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                       _ => panic!("bad input!"),

     

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                   }

     

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               })

     

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               .collect();

     

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           let part_1 = &input.iter().fold(0_u64, |acc, v| {

     

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               (v.start..=v.end).fold(acc, |acc, n| {

     

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                   if n <= 10 {

     

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                       return acc;

     

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                   }

     

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                   let len = n.ilog10() + 1;

     

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                   if len % 2 == 1 {

     

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                       return acc;

     

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                   }

     

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                   let pow = 10_u64.pow(len / 2);

     

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                   if n / pow == n % pow {

     

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                       return acc + n;

     

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                   }

     

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                   acc

     

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               })

     

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           });

     

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           println!("{}", part_1);

     

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           let part_2 = &input.iter().fold(0_u64, |acc, v| {

     

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               (v.start..=v.end).fold(acc, |acc, n| {

     

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                   if n <= 10 {

     

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                       return acc;

     

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                   }

     

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                   let len = n.ilog10() + 1;

     

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                   match (1..=len / 2).rfind(|clen| {

     

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                       let num = n % 10_u64.pow(*clen);

     

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                       let res = (0..len / clen).fold(0, |acc, i| acc + num * 10_u64.pow(i * clen));

     

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                       res == n

     

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                   }) {

     

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                       Some(_) => acc + n,

     

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                       _ => acc,

     

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                   }

     

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               })

     

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           });

     

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           println!("{}", part_2);

     

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       }