Can you cheat death by solving this riddle? - Shravan S K

譯者: Lilian Chiu 審譯者: Amanda Zhu

You and your best friend Bill are the greatest bards in the kingdom—

你和摯友比爾是王國中 最偉大的吟遊詩人——

but maybe not the brightest.

但可能不是最聰明的。

The hit song you performed at last night’s fair insulted the king,

昨晚你在集市表演的 熱門歌曲侮辱了國王，

and now your hours are numbered.

現在，你的死期將至。

Just before your execution,

在你被處死之前，

you’re approached by the princess, who happens to be a big fan.

公主上前來找你，她剛好是鐵粉。

She slips you a pouch containing two magic, six-sided dice

她偷偷塞給你一個小袋子， 內有兩個六面的魔法骰子，

that can land any way you wish.

可擲出你希望的那一面。

You have no idea how this could possibly help, but you thank her anyways.

你完全不知道這有什麼幫助，

但你仍然向她致謝。

As everything goes dark,

天色變暗後，

you both suddenly find yourself standing in a deep cavern before a robed figure.

你們兩人突然發現自己 站在一個很深的山洞裡，

前面有個穿長袍的人。

It turns out that Death is a connoisseur of most excellent music.

原來死神竟然是頂級音樂的鑑賞家。

He’s decided to give you a chance to escape your fate

他決定給你一個機會 逃離死亡的命運，

by beating him at his favorite game: life-sized Snakes and Ladders.

方法就是在他最喜歡的比賽中打敗他：

真人大小的蛇梯棋。

The cavern has 100 rooms connected by passageways

山洞中有一百個房間以通道相連，

as well as— you guessed it— snakes and ladders.

以及——你也猜到了——蛇和梯子。

Each turn one of you will roll a die, then advance that many rooms.

每一輪，你們有一人要擲骰子，

擲出幾點就移動幾間房間。

Ending your move at the bottom of a ladder means moving up to the top,

如果走到梯子的底端，

就得要移動到梯子頂端，

while ending on a snake’s head will make you slide down to its tail.

如果走到蛇的頭上， 你就會下滑到牠的尾巴。

Each of you must make your way through the cavern

你們兩人都得要在山洞中移動，

and reach the exit in fewer turns than Death himself.

最後抵達出口，

且使用的次數不能比死神多。

Before you can think twice, your host starts casting his die,

你都還沒機會三思， 死神就開始擲骰子了，

and within 6 rolls he’s reached the cavern entrance.

擲了六次之後，

他就抵達了洞口。

“Better get moving,” he says.

他說：「來吧！快！喔，順道一提，

“Oh, and by the way, once one of you uses a snake or ladder,

你們當中有人用過的蛇或梯子，

it’ll disappear and be inaccessible to the other.”

用完便會消失， 另一人就無法使用了。」

You have no idea how you can possibly get lucky enough to win,

你覺得你不可能有運氣贏得這場遊戲，

but then you remember your magic dice.

但接著，你想起了你的魔法骰子。

Can you figure out a sequence of rolls that will get both of you to the exit

你能想出要依序擲出什麼數字，

才能讓你們兩人分別都在 五輪之內移動到出口？

in 5 or fewer moves each?

Pause here to figure it out yourself. Answer in 3

［若要自行作答，在此暫停。 答案公佈倒數：3］

Answer in 2

［2］

Answer in 1

［1］

The cavern contains many routes to the exit,

山洞中有許多條路徑都能通到出口，

and it’s natural to gravitate to the ladders

你自然會想用梯子

that allow you to cover a lot of ground, quickly.

來讓你能快速移動很長的距離。

Like this one— on turn 2 you’d be at 75,

比如走這座梯子—— 在第二輪你就會走到 75，

but without any further ladder boosts, you’d need another 5 rolls to get out.

但沒有其他梯子幫忙，

你還需要擲五次骰子才能出去。

Or this one— three ladders get you to 82,

換這種走法—— 三座梯子讓你抵達 82，

but then it would take another 4 rolls to get around the pesky snake at 88.

但接著需要再擲四次骰子

才能跳過 88 上面這條麻煩的蛇。

In fact, there’s no path that can get you to the exit

事實上，沒有任何路徑

能讓你光靠梯子移動五次

in 5 moves using exclusively ladders.

就抵達出口。

So where does that leave you?

那你剩下什麼選擇？蛇。

Snakes.

It’s counterintuitive to make moves that take you farther away

直覺上你不會選擇

帶你遠離目的地的路徑。

from your target,

but snakes open up a surprising amount of opportunities.

但蛇所帶來的機會比你想像的多。

For instance, these three ladders would put you a single roll from the exit,

比如，

這三座梯子能讓你只要 再擲一次骰子就能抵達出口，

but cost too many turns to reach by ladders.

但要靠梯子抵達這些梯子 需要太多輪。

These two are, however, only 5 and 12 rooms from snake tails, respectively.

然而，這兩座梯子

距離蛇尾巴分別只有 五間和十二間房間的距離。

So could you work backwards from those to find a 5 roll path?

你是否能從那些地方往回推，

找到五輪就能走到的路徑？

There are exactly two 5-turn routes you might find using these ladders:

剛剛好有兩條骰五輪的路線，

用剛才說的梯子可以辦到：

Ladder snake snake ladder exit,

梯子、蛇、蛇、梯子、出口，

and ladder ladder snake ladder exit.

以及，

梯子、梯子、蛇、梯子、出口。

So that’s it, right? Unfortunately, no—

就這樣了，對吧？

很不幸，並不是這樣——

the two paths share a snake and a ladder,

這兩條路徑共用了 一座梯子和一條蛇，

each of which will be unusable after the first of you slides and then climbs.

先走的人滑下去再爬上去之後，

這梯子和蛇就不能再用了。

You won’t find 5-turn moves anywhere else,

要用到最後那座梯子， 已經沒有其他五輪的走法，

so is one of you doomed?

所以有一人死定了嗎？

There’s one more possibility to consider:

還有一個可能性要考量：

the disappearing ladders and snakes can impede your progress,

消失的梯子和蛇會妨礙你前進，

but could they also help it?

但是否也會幫你用其他路線？

There are two paths to the 94 ladder that almost work,

有兩條通到 94 的路徑，

幾乎可以成功，就多了這條蛇，

except for this snake,

at exactly the midpoint between the two ladders.

牠剛好位在兩座梯子間會停留的地方。

If Bill were to take that snake on his route,

如果比爾先走的路徑包括這條蛇，

you could then get past it and up to the exit in just 5 moves.

你就可以通過，

只需要五輪就能抵達出口。

And good news— whichever path you choose,

好消息——不論你選擇的是 這兩條路徑中的哪一條，

one of the 5-roll paths we found earlier does exactly that

我們先前找到的五輪路徑當中就有一條

剛好不需要走你用的蛇或梯子 就可抵達出口。

without using any of your snakes or ladders.

So all you need is for Bill to go first and stick to the plan.

所以只要讓比爾先走並照著計畫前進。

You and Bill both reach the cavern entrance

你和比爾都抵達了洞口，

and climb back into the public square, to everyone’s surprise.

爬回了公共廣場，

讓大家大吃一驚。

Before the guards can seize you again,

在守衛能再次抓住你之前，

you wow the crowd— and king— with a song about your epic contest with Death.

你表演了一首曲子， 講述你和死神之間的英勇競賽，

讓群眾，也包括了國王，為之驚艷。