Re-wrote the program to accept the netmask as an argument

README.md

@@ -1,6 +1,6 @@
 # subnetcalc #
 A very simple subnet calculator written in C. It's nothing fancy at all,
-just a small project of mine to get going with C.
+just a small project of mine to get me going with C.
 
 Simply build it (make), run it (./subnetcalc) and enter the subnet 
 mask in slash notation but without the slash. 
@@ -8,3 +8,11 @@ For example enter 24 for a 24-bit subnet mask and the
 program will output the total number of addresses in the range aswell
 as the total number of usable address for hosts.
 
+You can also give the netmask to the program as an argument. For example:
+
+    $> ./subnetcalc 24
+    Netmask bit: 24
+
+    256 total addresses
+    254 usable addresses for hosts
+