<PackageReference Include="BouncyCastle.Cryptography" Version="2.7.0" />

Org.BouncyCastle.Pqc.Crypto.Hqc.ReedMuller

static class ReedMuller
public static void Decode(byte[] m, ulong[] codeword, int n1, int mulParam)

public static void Encode(ulong[] codeword, byte[] m, int n1, int mulParam)