peuler 0.1.0

A Rust crate with solutions to the Project Euler problems
Documentation 
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use crate::Solution;

problem!(Problem0008, 8, "Largest Product in a Series");

impl Solution for Problem0008 {
    fn solve(&self) -> String {
        const INPUT: &str = "7316717653133062491922511967442657474235534919493496983520312774506326239578318016984801869478851843858615607891129494954595017379583319528532088055111254069874715852386305071569329096329522744304355766896648950445244523161731856403098711121722383113622298934233803081353362766142828064444866452387493035890729629049156044077239071381051585930796086670172427121883998797908792274921901699720888093776657273330010533678812202354218097512545405947522435258490771167055601360483958644670632441572215539753697817977846174064955149290862569321978468622482839722413756570560574902614079729686524145351004748216637048440319989000889524345065854122758866688116427171479924442928230863465674813919123162824586178664583591245665294765456828489128831426076900422421902267105562632111110937054421750694165896040807198403850962455444362981230987879927244284909188845801561660979191338754992005240636899125607176060588611646710940507754100225698315520005593572972571636269561882670428252483600823257530420752963450";
        let input_data = INPUT
            .chars()
            .map(|c| c.to_digit(10).unwrap() as u8)
            .collect::<Vec<_>>();

        let mut data = input_data.as_slice();
        let mut max_product = 0;
        let mut update_max_product = |current_data: &[u8]| {
            if current_data.len() >= 13 {
                let mut i = 0;
                let mut j = 13;
                let mut product = current_data[i..j].iter().map(|&n| n as u64).product();
                max_product = max_product.max(product);
                while j < current_data.len() {
                    product = product / (current_data[i] as u64) * (current_data[j] as u64);
                    i += 1;
                    j += 1;
                    max_product = max_product.max(product);
                }
            }
        };

        while let Some(pos) = data.iter().position(|&x| x == 0) {
            update_max_product(&data[..pos]);
            data = &data[(pos + 1)..];
        }
        update_max_product(data);

        max_product.to_string()
    }
}