The British intelligence and security organisation GCHQ released a “grid-shading puzzle” over Christmas to keep recipients entertained over the holiday season.
But so far, no one has been able to solve it and it’s giving codebreakers a headache with less than 24 hours left until the deadline.
Around 30,000 people, roughly 5% of the people who have tried their hand at it, have reached the final stage of the puzzle.
In a statement released by the spy agency, which also works in conjunction with SIS and MI5 — close to 600,000 people have managed to successfully solve the first stage of the puzzle which was “a nonogram which when completed correctly, creates a QR (Quick Response) code.”
But Director GCHQ, Robert Hannigan, has given a clue to the remaining codebreakers:
“With a few days to go no one has cracked it all yet, so my one and only clue is: it’s not as abstract as you think.
“What I hope the stages of the puzzle show is that to deliver our mission and keep Britain safe, we need people from all backgrounds, with all skills, who look at problems from every angle.”
You can find the final puzzle here.
But first, have a crack at the first puzzle below. The result is a QR code that your phone can read:
In this type of grid-shading puzzle, each square is either black or white. Some of the black squares have already been filled in for you.
Each row or column is labelled with a string of numbers. The numbers indicate the length of all consecutive runs of black squares, and are displayed in the order that the runs appear in that line. For example, a label “2 1 6” indicates sets of two, one and six black squares, each of which will have at least one white square separating them.
The deadline for the challenge is Monday February 1 at 10:59 (AEDT).
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