cp_library_rs/data_structure/
acc3d.rs

1//! 2次元累積和
2
3use num_traits::Num;
4
5/// acc3D
6/// - 3次元累積和を取る
7///
8/// **戻り値**
9/// - `|lx, rx, ly, ry, lz, rz|: (usize, usize, usize, usize, usize, usize) -> T`
10#[allow(clippy::ptr_arg)]
11pub fn acc3D<T: Num + Copy>(
12    array: &Vec<Vec<Vec<T>>>,
13) -> impl Fn(usize, usize, usize, usize, usize, usize) -> T {
14    let (X, Y, Z) = (array.len(), array[0].len(), array[0][0].len());
15    let mut S = vec![vec![vec![T::zero(); Z + 1]; Y + 1]; X + 1];
16
17    for i in 0..X {
18        for j in 0..Y {
19            for k in 0..Z {
20                S[i + 1][j + 1][k + 1] = array[i][j][k]
21                    + (S[i + 1][j + 1][k] + S[i + 1][j][k + 1] + S[i][j + 1][k + 1])
22                    + S[i][j][k]
23                    - (S[i + 1][j][k] + S[i][j + 1][k] + S[i][j][k + 1]);
24            }
25        }
26    }
27
28    move |lx, rx, ly, ry, lz, rz| -> T {
29        S[rx][ry][rz] + (S[lx][ly][rz] + S[lx][ry][lz] + S[rx][ly][lz])
30            - (S[lx][ry][rz] + S[rx][ly][rz] + S[rx][ry][lz])
31            - S[lx][ly][lz]
32    }
33}