Function convolution_i64 

pub fn convolution_i64(a: &[i64], b: &[i64]) -> Vec<i64>

Calculates the $(+, \times)$ convolution in i64.

See the module-level documentation for more details.

Returns a empty Vec if a or b is empty.

Constraints

• $|a| + |b| - 1 \leq 2^{24}$
• All elements of the result are inside of the range of i64

Complexity

• $O(n \log n)$ where $n = |a| + |b|$.

Example

use proconio::{input, source::once::OnceSource};

input! {
    from OnceSource::from(
        "3\n\
         1 2 3\n\
         3\n\
         -1 -2 -3\n",
    ),
    a: [i64],
    b: [i64],
}

assert_eq!(
    ac_library::convolution_i64(&a, &b),
    [-1, -4, -10, -12, -9],
);