This program is stupid.

It's an opinion, not an issue.

Ok, Karen.

A number m of the form 10x + y is divisible by 7 if and only if x − 2y is divisible by 7.

m = 1603 -> 160 - (2 x 3) -> 154             //first time
154 -> 15 - 8 = 7 and 7 is divisible by 7    //second time

Read the description again, please.

This program is stupid. It forces the computer to think in the way humans think, which is essentially inefficient for a machine to do.

NOT TO MENTION it is a redundant program. You're writing a program to figure out whether a goddamn number is dividible by 7 (%7 == 0), and you went through a bunch of unnecessary operations to eventually use the condition %7 == 0 ? again. How dumb is that?