// Type aliases for network addresses
typedef UUID = bit<128>
typedef IP4 = bit<32>
typedef NetMask = bit<32>

// Input relations for hosts and subnets
input relation Host(id: UUID, name: string, ip: IP4)
input relation Subnet(id: UUID, prefix: IP4, mask: NetMask)

// Output relation mapping hosts to subnets
output relation HostInSubnet(host: UUID, subnet: UUID)

// Rule: compute host-to-subnet mappings using bitwise filtering
HostInSubnet(host_id, subnet_id) :-
    Host(host_id, _, host_ip),
    Subnet(subnet_id, subnet_prefix, subnet_mask),
    ((host_ip & subnet_mask) == subnet_prefix).