Erik Demaine and Martin Demaine's Puzzles:

CSAIL Annual Meeting 2019 Puzzle

In what has become a regular event, Erik Demaine and Martin Demaine give out puzzles each year at our lab's Annual Meeting. Here is the 2019 edition.

This puzzle features a (partial) custom font we designed in the style of the MIT logo.

Puzzle 1 is based on the “Three in a row” puzzle by Robert E. Neale from 2017. Puzzle 2 is loosely based on map-folding puzzles (such as those described by Martin Gardner, in this paper (Figure 12), or on this website).

Two-page PDF (print duplex, flipping on long edge)

Front side:

[72dpi] [150dpi] [PDF]
Back side:

[72dpi] [150dpi] [PDF]


The puzzle starts as a 3 × 3 square with three slits (of length 1) forming a U shape. You can fold the puzzle only along the grid lines. There are two different goals/puzzles:

  1. Puzzle 1: Form a 1 × 3 strip showing exactly one red square, exactly one green square, and exactly one blue square (in any order, or in exactly this order).
  2. Puzzle 2: Form a 1 × 1 square packet so that the layers spell, in order, M-I-T-C-S-A-I-L. (Observe that each square has the same letter on both sides.) You should also be able to arrange for the instructions panel to be at the very beginning or end of the sequence.

Printing Notes

This puzzle requires printing images on both sides with fairly close alignment. This can require some fiddling with your printer or photocopier.

The puzzle was designed for color printing. If you're using a black-and-white printer, try printing this grayscale version.

The PDF file is the best combination of printing quality and small file size. You will need a suitable viewer. Alternatively, you can print one of the images. If you can print images scaled to fit, use 150dpi. Otherwise, use 72dpi.

Last updated May 7, 2019 by Erik Demaine.Accessibility