--- Part Two ---

Packets sent to address 255 are handled by a device called a NAT (Not Always Transmitting). The NAT
is responsible for managing power consumption of the network by blocking certain packets and
watching for idle periods in the computers.

If a packet would be sent to address 255, the NAT receives it instead.  The NAT remembers only the
last packet it receives; that is, the data in each packet it receives overwrites the NAT's packet
memory with the new packet's X and Y values.

The NAT also monitors all computers on the network.  If all computers have empty incoming packet
queues and are continuously trying to receive packets without sending packets, the network is
considered idle.

Once the network is idle, the NAT sends only the last packet it received to address 0; this will
cause the computers on the network to resume activity.  In this way, the NAT can throttle power
consumption of the network when the ship needs power in other areas.

Monitor packets released to the computer at address 0 by the NAT.  What is the first Y value
delivered by the NAT to the computer at address 0 twice in a row?