And I thought uncomputability is only true for programs that don’t halt? A blank program can definitely be verified to halt.
For any single program, the question “does this program halt?” is computable, for a trivial reason. Either the program that prints “Yes” or the program that prints “No” correctly answers the question, although we might not know which one. The uncomputability of the halting problem is the fact that there is no program that can take as input any program whatever and say whether it halts.
For any single program, the question “does this program halt?” is computable, for a trivial reason. Either the program that prints “Yes” or the program that prints “No” correctly answers the question, although we might not know which one. The uncomputability of the halting problem is the fact that there is no program that can take as input any program whatever and say whether it halts.