1use ark_ff::PrimeField;
 2
 3use crate::utils::vec::*;
 4
 5#[derive(Debug, Clone, Eq, PartialEq)]
 6pub struct R1CS<F: PrimeField> {
 7    pub l: usize, // io len
 8    pub A: SparseMatrix<F>,
 9    pub B: SparseMatrix<F>,
10    pub C: SparseMatrix<F>,
11}
12impl<F: PrimeField> R1CS<F> {
13    /// returns a tuple containing (w, x) (witness and public inputs respectively)
14    pub fn split_z(&self, z: &[F]) -> (Vec<F>, Vec<F>) {
15        (z[self.l + 1..].to_vec(), z[1..self.l + 1].to_vec())
16    }
17}
18
19#[cfg(test)]
20pub mod tests {
21    use super::*;
22    use crate::utils::vec::tests::{to_F_matrix, to_F_vec};
23
24    pub fn get_test_r1cs<F: PrimeField>() -> R1CS<F> {
25        // R1CS for: x^3 + x + 5 = y (example from article
26        // https://www.vitalik.ca/general/2016/12/10/qap.html )
27        let A = dense_matrix_to_sparse(to_F_matrix::<F>(vec![
28            vec![0, 1, 0, 0, 0, 0],
29            vec![0, 0, 0, 1, 0, 0],
30            vec![0, 1, 0, 0, 1, 0],
31            vec![5, 0, 0, 0, 0, 1],
32        ]));
33        let B = dense_matrix_to_sparse(to_F_matrix::<F>(vec![
34            vec![0, 1, 0, 0, 0, 0],
35            vec![0, 1, 0, 0, 0, 0],
36            vec![1, 0, 0, 0, 0, 0],
37            vec![1, 0, 0, 0, 0, 0],
38        ]));
39        let C = dense_matrix_to_sparse(to_F_matrix::<F>(vec![
40            vec![0, 0, 0, 1, 0, 0],
41            vec![0, 0, 0, 0, 1, 0],
42            vec![0, 0, 0, 0, 0, 1],
43            vec![0, 0, 1, 0, 0, 0],
44        ]));
45
46        R1CS::<F> { l: 1, A, B, C }
47    }
48
49    pub fn get_test_z<F: PrimeField>(input: usize) -> Vec<F> {
50        // z = (1, io, w)
51        to_F_vec(vec![
52            1,
53            input,                             // io
54            input * input * input + input + 5, // x^3 + x + 5
55            input * input,                     // x^2
56            input * input * input,             // x^2 * x
57            input * input * input + input,     // x^3 + x
58        ])
59    }
60}