Write down the subnet mask that makes the following two hosts $($IPs$)$ on the same subnet? Write the subnet with least number of hosts.

The hosts are $192\mathrm{.}168\mathrm{.}0\mathrm{.}99$ and $192\mathrm{.}168\mathrm{.}1\mathrm{.}100$

If the answer is $255\mathrm{.}255\mathrm{.}0.$ that it that way. Don't includes any slash or comma or period or anything else.