What is invalid input detected at marker?

On which device would you use the no ip domain lookup command?

I want a script that will run for all ip's in my house, and ping them.

I was hoping for something like this: there is no looping involved. I just need a list of my ip's (192.168.) and the time it took to get to each.
thats it. no looping, no ping to test ping latency, etc. Just a list.
b0x do you have an IP range? yeah, 192.1-192.254
b0x so why not use nslookup? thats why I was hoping to avoid nslookup. itll work on every device at home. But I need something that I can execute from the terminal on my tablet.
b0x: "dns bla bla". b0x dnsbl.com b0x: if its only one ip you could make a script that ping that ip and save the time in a file. that's what i've been looking for. if its more then just one ip you need a script.

What is invalid input detected at marker?

I am writing an app that calculates the area of a rectangle, with the width and height of the rectangle inputted as integers.

My question is about the "marker" that is given to indicate where the inputted integers are invalid, such as not being a whole number.

Is it safe for my program to assume the invalid input is at the marker, or should I check if the numbers are at the marker before I start calculating the area? You can assume that you're given the markers in a way that is well-defined, ie it's a valid place to end the input. If you assume that there is some point in the input that's invalid, then it would be an error for your program to do anything with the invalid part. So you're safe, assuming the input is valid.