You wake lying face down on a hard stone floor. Your head hurts. As your eyes find focus, you see a haiku scratched into the ground beside you:
A wrong step brings death!
But, a wrong guess brings knowledge…
Read. Learn. Live. Escape.
Death? Escape? You leap up and scan your surroundings... You're in a large smooth-walled cavern, whose floor is made entirely of a grid of seemingly floating stone platforms, suspended somehow over an immeasurable drop. The only way out appears to be a doorway on the far side of the room. As you stare, you notice that each platform has a single letter carved into it. You quickly note them down:
$$ \begin{matrix} \fbox{R} & \fbox{U} & \fbox{Y} & \fbox{E} & \fbox{R} & \fbox{O} & \color{blue}{\fbox{▲}} & \fbox{L} & \fbox{N} & \fbox{R} & \fbox{A} & \fbox{E} & \fbox{Y} \\ \fbox{A} & \fbox{R} & \fbox{D} & \fbox{Y} & \fbox{E} & \fbox{E} & \fbox{R} & \fbox{U} & \fbox{O} & \fbox{F} & \fbox{M} & \fbox{O} & \fbox{T} \\ \fbox{C} & \fbox{U} & \fbox{L} & \fbox{A} & \fbox{A} & \fbox{T} & \fbox{Y} & \fbox{L} & \, & \fbox{S} & \fbox{A} & \fbox{I} & \, & \\ \fbox{B} & \fbox{T} & \fbox{W} & \fbox{O} & \fbox{T} & \fbox{H} & \fbox{E} & \fbox{N} & \fbox{D} & \fbox{I} & \fbox{I} & \fbox{W} & \fbox{N} \\ \fbox{E} & \fbox{E} & \fbox{D} & \fbox{E} & \fbox{O} & \fbox{R} & \fbox{M} & \fbox{F} & \fbox{D} & \fbox{A} & \fbox{D} & \fbox{N} & \fbox{E} \\ \fbox{N} & \fbox{L} & \fbox{N} & \fbox{I} & \fbox{R} & \fbox{S} & \fbox{R} & \fbox{A} & \fbox{E} & \fbox{N} & \fbox{M} & \fbox{I} & \, \\ \fbox{O} & \fbox{A} & \fbox{E} & \fbox{R} & \fbox{O} & \fbox{M} & \fbox{T} & \fbox{B} & \fbox{U} & \fbox{A} & \fbox{R} & \fbox{O} & \fbox{T} \\ \fbox{K} & \fbox{A} & \fbox{E} & \fbox{T} & \, & \fbox{E} & \fbox{C} & \fbox{N} & \fbox{O} & \fbox{D} & \fbox{A} & \fbox{E} & \fbox{R} \\ \fbox{A} & \, & \fbox{E} & \fbox{A} & \fbox{P} & \fbox{T} & \fbox{H} & \fbox{A} & \fbox{N} & \, & \fbox{T} & \fbox{O} & \fbox{P} \\ \fbox{T} & \fbox{A} & \fbox{F} & \fbox{S} & \fbox{Y} & \fbox{E} & \, & \fbox{O} & \fbox{S} & \fbox{A} & \fbox{G} & \fbox{I} & \fbox{O} \\ \fbox{O} & \fbox{H} & \fbox{E} & \fbox{P} & \fbox{R} & \fbox{F} & \fbox{R} & \fbox{O} & \fbox{M} & \fbox{T} & \fbox{H} & \fbox{E} & \fbox{T} \\ \fbox{U} & \fbox{Y} & \fbox{O} & \fbox{N} & \fbox{O} & \fbox{W} & \fbox{E} & \fbox{S} & \fbox{E} & \fbox{A} & \fbox{M} & \fbox{T} & \fbox{I} \\ \fbox{D} & \fbox{N} & \fbox{A} & \color{green}{\fbox{▲}} & \fbox{C} & \fbox{S} & \fbox{P} & \fbox{E} & \fbox{A} & \fbox{E} & \fbox{S} & \fbox{O} & \fbox{G} \\ \end{matrix} $$
You're standing on the platform represented by the green arrow ($\color{green}{▲}$) in the bottom row. To reach the door, and thus freedom, you need to cross the room to the platform on the far side indicated by the blue arrow ($\color{blue}{▲}$). You take a breath to calm yourself and make the following observations:
- The platforms are large, but if necessary, you estimate that you could safely jump completely over one to another, as well as jump diagonally between them, though not completely over one on the diagonal (I.e. from $\color{green}{▲}$, you could safely reach any of the nearby $\text{N}$, $\text{A}$, $\text{C}$, $\text{S}$, $\text{O}$, $\text{N}$, $\text{O}$, and $\text{P}$ platforms - [see addendum at the bottom of this post for an example])
- The platforms are too spaced out to spread your weight between more than one at a time, so when jumping you're going to have to commit yourself fully and assume, based on the haiku, that leaping to any invalid platform, will result in it collapsing, leading to death
- There are some missing platforms in the grid, which can obviously be jumped over if necessary, but are otherwise impassible
What platforms can you safely traverse in order to escape?
You're only going to get one shot at this, so you better be damn sure of your path before you take that first leap...
For convenience, here's an ascii/csv version of the floor tiles, since MathJax seems to render matrices in columns:
R,U,Y,E,R,O,▲,L,N,R,A,E,Y,
A,R,D,Y,E,E,R,U,O,F,M,O,T,
C,U,L,A,A,T,Y,L, ,S,A,I, ,
B,T,W,O,T,H,E,N,D,I,I,W,N,
E,E,D,E,O,R,M,F,D,A,D,N,E,
N,L,N,I,R,S,R,A,E,N,M,I, ,
O,A,E,R,O,M,T,B,U,A,R,O,T,
K,A,E,T, ,E,C,N,O,D,A,E,R,
A, ,E,A,P,T,H,A,N, ,T,O,P,
T,A,F,S,Y,E, ,O,S,A,G,I,O,
O,H,E,P,R,F,R,O,M,T,H,E,T,
U,Y,O,N,O,W,E,S,E,A,M,T,I,
D,N,A,▲,C,S,P,E,A,E,S,O,G,
Edit: To be 100% clear about "legal" moves (i.e. jumps that you're physically capable of making), here's a diagrammatic version of the explanation:
$$ \begin{matrix} \color{red}{\fbox{A}} & \color{red}{\fbox{B}} & \color{blue}{\fbox{C}} & \color{red}{\fbox{D}} & \color{red}{\fbox{E}} \\ \color{red}{\fbox{F}} & \color{blue}{\fbox{G}} & \color{blue}{\fbox{H}} & \color{blue}{\fbox{I}} & \color{red}{\fbox{J}} \\ \color{blue}{\fbox{K}} & \color{blue}{\fbox{L}} & \color{green}{\fbox{●}} & \color{blue}{\fbox{M}} & \color{blue}{\fbox{N}} \\ \color{red}{\fbox{O}} & \color{blue}{\fbox{P}} & \color{blue}{\fbox{Q}} & \color{blue}{\fbox{R}} & \color{red}{\fbox{S}} \\ \color{red}{\fbox{T}} & \color{red}{\fbox{U}} & \color{blue}{\fbox{V}} & \color{red}{\fbox{W}} & \color{red}{\fbox{X}} \\ \end{matrix} $$
So if you were standing on the green dot ($\color{green}{●}$) in the centre, you would be able to safely jump to any of the blue letters ($\text{C}$, $\text{G}$, $\text{H}$, $\text{I}$, $\text{K}$, $\text{L}$, $\text{M}$, $\text{N}$, $\text{P}$, $\text{Q}$, $\text{R}$ and $\text{V}$). If any of those platforms were missing, you obviously couldn't land there, however, if $\text{H}$, $\text{L}$, $\text{M}$, or $\text{Q}$ were missing, you could still reach $\text{C}$, $\text{K}$, $\text{N}$, or $\text{V}$.
