dsalgo 0.3.10

A package for Datastructures and Algorithms.
Documentation 
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use crate::accumulate_iterator::accumulate;

pub fn factorial_table<T>(size: usize) -> Vec<T>
where
    T: std::ops::Mul<Output = T> + From<u64> + Clone,
{
    if size == 0 {
        return vec![];
    }

    let mut v = (0..size as u64).map(|i| i.into()).collect::<Vec<T>>();

    v[0] = 1.into();

    let op = |a: T, b: T| -> T { a * b };

    accumulate(&op, v.into_iter()).collect()
}

#[cfg(test)]

mod tests {

    use super::*;

    #[test]

    fn test() {
        use crate::{
            default_static_modular_arithmetic::Modular1_000_000_007,
            modular_int_with_arithmetic::Modint,
        };

        type Mint = Modint<u32, Modular1_000_000_007>;

        let res = factorial_table::<Mint>(20)
            .into_iter()
            .map(|x| x.value())
            .collect::<Vec<u32>>();

        assert_eq!(
            res,
            [
                1, 1, 2, 6, 24, 120, 720, 5040, 40320, 362880, 3628800,
                39916800, 479001600, 227020758, 178290591, 674358851,
                789741546, 425606191, 660911389, 557316307
            ],
        );
    }
}