How can we tell Subnet Mask for 2 ips 171.43.22.5 192.168.0.1?

 Default subnet mask of the IPs are 255.255.255.0 and 255.255.0.0 respectively. But if just an IP is given, it  may be in any IP pool. We can't tell the subnet mask of just an IP. We should get the subnet bit count.

Your question is unclear if you mean what is the default subnet of these two ip’s  then here it is

192.168.0.1 = 255.255.255.0

171.43.22.5 = 255.255.0.0

192.168.0.1 is a private IP and 171.43.22.5 is  public IP whatever ISP has given you this Public IP must have subneted it.  The subnet of this particular public ip should be 255.255.255.252, you can have the same subnet on 192.168.0.1 if you are using point to point connection. this subnet gives you 2 usable ip's....... its a /30 address scheme

if it is not subnetting than default subnet mask

171.43.0.0/16  & 192.168.0.0/24

i think for 171 it's 255.255.0.0

and for 192 it's 255.255.255.0