DAVID J. MALAN: So that last program had a bug whereby it reported that 0 is negative, even though technically 0 is neither positive nor negative. But not a problem. We can fix this bug by inserting another condition into our program. Specifically, at line 12 I'm going to hit Enter. And then add else if and equals equals 0, open curly brace, close curly brace. Now you'll notice that I said and typed equals equals as opposed to just equals. Now that's simply because C is already using a single equal sign as the so-called assignment operator and in order to assign a value from the right to a, say, variable on the left. But in this case, we actually want to test n for equality with 0. And to do that in C, you simply have to remember to use two equal signs. Well, if n does indeed equal equal 0, I'm going to print out the following instead. Print F, you picked 0. Save my file. And now let's compile this as conditions 1. Back at my blinking prompt, I'm going to run the program with dot slash, conditions 1. And let's do that same sanity check again as before. 1 for my int, which is indeed positive. Let's rerun this as conditions 1 with a second input of, say, negative 1, which is indeed negative. Now let's test it with 0. dot slash, conditions 1. Enter. 0 and-- phew. I indeed picked 0 this time.