use num_traits::Num;
#[allow(clippy::ptr_arg)]
pub fn acc3D<T: Num + Copy>(
array: &Vec<Vec<Vec<T>>>,
) -> impl Fn(usize, usize, usize, usize, usize, usize) -> T {
let (X, Y, Z) = (array.len(), array[0].len(), array[0][0].len());
let mut S = vec![vec![vec![T::zero(); Z + 1]; Y + 1]; X + 1];
for i in 0..X {
for j in 0..Y {
for k in 0..Z {
S[i + 1][j + 1][k + 1] = array[i][j][k]
+ (S[i + 1][j + 1][k] + S[i + 1][j][k + 1] + S[i][j + 1][k + 1])
+ S[i][j][k]
- (S[i + 1][j][k] + S[i][j + 1][k] + S[i][j][k + 1]);
}
}
}
move |lx, rx, ly, ry, lz, rz| -> T {
S[rx][ry][rz] + (S[lx][ly][rz] + S[lx][ry][lz] + S[rx][ly][lz])
- (S[lx][ry][rz] + S[rx][ly][rz] + S[rx][ry][lz])
- S[lx][ly][lz]
}
}