Yes, a bad implementation, resulting from doing online editing with the head under the arm.

I originally wrote it as:

unsigned char next[6] = {1,2,3,4,5,0};
unsigned char n = 0;
for (;;) {
    if (pressed) break;
    n = next[n];
}
n = 1 << n;

I.e. using the same concept as the second snippet. This is a big danger with editing/posting code on one monitor, and looking at a movie on another :)

Directly using the table entries is of course only allowed when they form a closed set within the [0..n) range.