TedTest

From the Ted Talk by Dennis Shasha: Can you solve the temple riddle?

Unscramble the Blue Letters

You've found the hidden switches, evaded the secret traps, and now your expedition finally stands at the heart of the ancient tmplee inside The Lost City. But as you study the itprnsiocnis in the near tatol darkness, two of the eight graduate students accompanying you bump into the alter. Suddenly, two whisps of green smoke burst forth and the walls begin to shake. Fleeing for your lives, you come to a room you passed before with five hayawlls, including the one to the aaltr and the one leindag back outside. The giant sandglass in the cteenr is now flowing, with less than an hour before it emtpeis, and the rnlumbig tells you that you don't want to be around when that happens. From what you rcaell of your way here, it would take about 20 minutes to reach the exit at a fast pace. You know this is the last junction before the exit, but your trail mgrknais have been erased, and no one remembers the way. If nine of you split up, there should be just enough time for each group to explore one of the four halls ahead and report back to this room, with everyone then making a run down the correct path. There's just one problem; the inscriptions told of the altar's curse: the spirits of the city's King and Queen possessing intruders and leading them to their doom through deception. riremebemng the green smoke, you relzaie two of the setdtuns have been cursed. At any time, one or both of them might lie, though they also might tell the tutrh. You know for sure that the curse didn't get you, but you don't know which students can't be trusted, and because the possessed students may lie only occasionally, there is no guaranteed way to test them to determine which are cursed. Can you figure out a way to ensure that you all escape? Don't worry about the possessed students attacking or otherwise harming the others. This curse only affects their communication. Pause the video now if you want to figure it out by yourself! Answer in: 3 aesnwr in: 2 Answer in: 1 The first thing to realize is that since you know you aren't possessed, you can explore one of the halls alone. This leaves eight students for the rmineaing three paths. Sending groups of four down just two of the paths won't work because if one group came back split two versus two, you'd have to guess who to trust. But splitting them into one pair and two trios would work every time, and here's why. The peseosssd students might lie, or they might not, but you know there are only two of them, while the other six will always tell the truth. When each gourp rerntus to the hall, all of its mmbeers will either give the same report or argue about whether they found the exit. If a trio returns in total agreement, then you know none of them are lying. With the pair, you can't be sure either way, but all you need is raliblee evidence about three of the four phtas. The fourth you can fuigre out using the pcesors of elimination. Of course, none of this matters if you're lucky enough to find the exit yourself, but otherwise, putting everything together leaves you with three possibilities. If each group gives a consistent answer, either everyone is telling the truth, or the two possessed students are paired together. In either case, ignore the duo. If there's only one group arguing, both others must be telling the truth, and if there are two conflicts, then the possessed students are in separate gruops and you can sfelay trust the majority in both trios since at least two people in each will be truthful. The temple collapses behind you as greenish vapors escape from two of the students. You're all safe and free from the curse. After that ordeal, you tell your group they all deserve a voacitan, and you just happen to have another eieotidpxn coming up.

Open Cloze

You've found the hidden switches, evaded the secret traps, and now your expedition finally stands at the heart of the ancient ______ inside The Lost City. But as you study the ____________ in the near _____ darkness, two of the eight graduate students accompanying you bump into the alter. Suddenly, two whisps of green smoke burst forth and the walls begin to shake. Fleeing for your lives, you come to a room you passed before with five ________, including the one to the _____ and the one _______ back outside. The giant sandglass in the ______ is now flowing, with less than an hour before it _______, and the ________ tells you that you don't want to be around when that happens. From what you ______ of your way here, it would take about 20 minutes to reach the exit at a fast pace. You know this is the last junction before the exit, but your trail ________ have been erased, and no one remembers the way. If nine of you split up, there should be just enough time for each group to explore one of the four halls ahead and report back to this room, with everyone then making a run down the correct path. There's just one problem; the inscriptions told of the altar's curse: the spirits of the city's King and Queen possessing intruders and leading them to their doom through deception. ___________ the green smoke, you _______ two of the ________ have been cursed. At any time, one or both of them might lie, though they also might tell the _____. You know for sure that the curse didn't get you, but you don't know which students can't be trusted, and because the possessed students may lie only occasionally, there is no guaranteed way to test them to determine which are cursed. Can you figure out a way to ensure that you all escape? Don't worry about the possessed students attacking or otherwise harming the others. This curse only affects their communication. Pause the video now if you want to figure it out by yourself! Answer in: 3 ______ in: 2 Answer in: 1 The first thing to realize is that since you know you aren't possessed, you can explore one of the halls alone. This leaves eight students for the _________ three paths. Sending groups of four down just two of the paths won't work because if one group came back split two versus two, you'd have to guess who to trust. But splitting them into one pair and two trios would work every time, and here's why. The _________ students might lie, or they might not, but you know there are only two of them, while the other six will always tell the truth. When each _____ _______ to the hall, all of its _______ will either give the same report or argue about whether they found the exit. If a trio returns in total agreement, then you know none of them are lying. With the pair, you can't be sure either way, but all you need is ________ evidence about three of the four _____. The fourth you can ______ out using the _______ of elimination. Of course, none of this matters if you're lucky enough to find the exit yourself, but otherwise, putting everything together leaves you with three possibilities. If each group gives a consistent answer, either everyone is telling the truth, or the two possessed students are paired together. In either case, ignore the duo. If there's only one group arguing, both others must be telling the truth, and if there are two conflicts, then the possessed students are in separate ______ and you can ______ trust the majority in both trios since at least two people in each will be truthful. The temple collapses behind you as greenish vapors escape from two of the students. You're all safe and free from the curse. After that ordeal, you tell your group they all deserve a ________, and you just happen to have another __________ coming up.

Solution

safely
rumbling
process
recall
total
hallways
answer
group
temple
empties
students
inscriptions
center
possessed
expedition
remembering
figure
markings
altar
remaining
leading
truth
groups
vacation
realize
reliable
members
returns
paths

Original Text

You've found the hidden switches, evaded the secret traps, and now your expedition finally stands at the heart of the ancient temple inside The Lost City. But as you study the inscriptions in the near total darkness, two of the eight graduate students accompanying you bump into the alter. Suddenly, two whisps of green smoke burst forth and the walls begin to shake. Fleeing for your lives, you come to a room you passed before with five hallways, including the one to the altar and the one leading back outside. The giant sandglass in the center is now flowing, with less than an hour before it empties, and the rumbling tells you that you don't want to be around when that happens. From what you recall of your way here, it would take about 20 minutes to reach the exit at a fast pace. You know this is the last junction before the exit, but your trail markings have been erased, and no one remembers the way. If nine of you split up, there should be just enough time for each group to explore one of the four halls ahead and report back to this room, with everyone then making a run down the correct path. There's just one problem; the inscriptions told of the altar's curse: the spirits of the city's King and Queen possessing intruders and leading them to their doom through deception. Remembering the green smoke, you realize two of the students have been cursed. At any time, one or both of them might lie, though they also might tell the truth. You know for sure that the curse didn't get you, but you don't know which students can't be trusted, and because the possessed students may lie only occasionally, there is no guaranteed way to test them to determine which are cursed. Can you figure out a way to ensure that you all escape? Don't worry about the possessed students attacking or otherwise harming the others. This curse only affects their communication. Pause the video now if you want to figure it out by yourself! Answer in: 3 Answer in: 2 Answer in: 1 The first thing to realize is that since you know you aren't possessed, you can explore one of the halls alone. This leaves eight students for the remaining three paths. Sending groups of four down just two of the paths won't work because if one group came back split two versus two, you'd have to guess who to trust. But splitting them into one pair and two trios would work every time, and here's why. The possessed students might lie, or they might not, but you know there are only two of them, while the other six will always tell the truth. When each group returns to the hall, all of its members will either give the same report or argue about whether they found the exit. If a trio returns in total agreement, then you know none of them are lying. With the pair, you can't be sure either way, but all you need is reliable evidence about three of the four paths. The fourth you can figure out using the process of elimination. Of course, none of this matters if you're lucky enough to find the exit yourself, but otherwise, putting everything together leaves you with three possibilities. If each group gives a consistent answer, either everyone is telling the truth, or the two possessed students are paired together. In either case, ignore the duo. If there's only one group arguing, both others must be telling the truth, and if there are two conflicts, then the possessed students are in separate groups and you can safely trust the majority in both trios since at least two people in each will be truthful. The temple collapses behind you as greenish vapors escape from two of the students. You're all safe and free from the curse. After that ordeal, you tell your group they all deserve a vacation, and you just happen to have another expedition coming up.

Frequently Occurring Word Combinations

ngrams of length 2

collocation	frequency
possessed students	5

Important Words

accompanying
affects
agreement
altar
alter
ancient
answer
argue
arguing
attacking
bump
burst
case
center
city
collapses
coming
communication
conflicts
consistent
correct
curse
cursed
darkness
deception
deserve
determine
doom
duo
elimination
empties
ensure
erased
escape
evaded
evidence
exit
expedition
explore
fast
figure
finally
find
fleeing
flowing
fourth
free
giant
give
graduate
green
greenish
group
groups
guaranteed
guess
hall
halls
hallways
happen
harming
heart
hidden
hour
ignore
including
inscriptions
intruders
junction
king
leading
leaves
lie
lives
lost
lucky
lying
majority
making
markings
matters
members
minutes
occasionally
ordeal
pace
pair
paired
passed
path
paths
pause
people
possessed
possessing
possibilities
process
putting
queen
reach
realize
recall
reliable
remaining
remembering
remembers
report
returns
room
rumbling
run
safe
safely
sandglass
secret
sending
separate
shake
smoke
spirits
split
splitting
stands
students
study
suddenly
switches
telling
tells
temple
test
time
told
total
trail
traps
trio
trios
trust
trusted
truth
truthful
vacation
vapors
video
walls
whisps
work
worry