carlini / printf-tac-toe Goto Github PK

You printf() program is not Turing complete as it require an external while() loop to work. It would be turing complete if this control structure was embedded inside the printf() arguments.

Posting on behalf of a friend:

There is a bug in the tic-tac-toe game. P1 wins if either player plays their piece on an occupied square.
Gotta use that GItHub "blame" button

The link should be to https://www.ioccc.org

Currently, it's to http://ioccc.org/ which doesn't resolve

this is super interesting!!

although i don't completely understand how this works, i just found a bug — if your opponent places their letter on position already taken by you they just win automatically.

[deleted]

Before reading my issue, please know that I'm very impressed with this, and I got a lot out of reading the README - thank you / really well done!

I'm using PuTTY v0.73 to access an Ubuntu 18.04 machine, compiled as per the README.

Step 1: Run, empty board is presented:

Step 2: Enter 5 and press Return:

Step 3: Enter 1 and press Return:

It turns out that the string PuTTY is sent to stdin... I've never quite figured out what causes these to occur, and I've seen them in the past too - mainly when accidentally writing binary data to stdout.

If I remove the PuTTY input with 5x Backspace then I can play the game... if I'm lucky...

However, I also notice that playing the following game, results in some "invisible" characters in the input buffer, allowing me to press backspace, and get the cursor to wrap back on to the previous line:

5, 1, 7, 3

If I do clear this "invisible" input, then the following game runs to completion:

5, 1, 7, 3, 2, 8, 4, 6, 9

If I don't clear this "invisible" intput (i.e: I only press 5x Backspace to remove the PuTTY, or multiple thereof), then the game goes wonky... it may run to the end, or it may make wrong statements.

I suspect that this "invisible" input is also related to PuTTY, hence putting all of this in a single issue.

You wrote

Computing the NOT of a single value is also easy:

printf("%1$255d%1$s%hhn", a, b)

will compute

*b = (strlen(a)+255)%256 = strlen(a)-1

and again, because strlen(x) is either 1 or 0 we have

*c = !b

Well,in *c=!b ,where does c come from? Do you mean *b=!a ?

Windows 10 LTSC 2019
TDM-GCC 9.2