The good news is that your experimental robo-ants are a success! The bad news is that you accidentally just gave them the ability to shoot deadly lasers …and you can’t turn it off. You have five minutes to stop them before the lasers go online.
好消息是,你的實驗性 機器螞蟻非常成功! 壞消息是,你不小心 給了它們發射致命雷射的能力…… 且你無法把它關掉。 你有五分鐘可以阻止它們, 然後雷射就會連線。 在那之前,你所有的機器螞蟻
Until then, all of your robo-ants will walk inside their habitat at a speed of exactly 1 meter per minute. If they bump into each other or hit a dead end, they’ll instantly turn around and walk back the way they came. When five minutes are up, they’ll turn on their lasers, break free, and stream out into the world, carving a path of destruction as they go.
都會在它們的棲息地裡行走, 速度剛好是每分鐘一公尺。 如果它們撞到或是碰到死路, 它們會馬上回轉,從原路走回去。 五分鐘過後,它們就會啟動雷射, 脫身獲得自由,湧入世界中, 所經之處都會造成毀滅。 你有一個機會阻止它們,
Your one chance to stop them is to insert the two emergency vacuum nozzles into the habitat and suck the ants up before they break free. The nozzles can press into any one location in the habitat through a membrane covering its front side, and any ants that walk past will be sucked up and deactivated. You can’t move the nozzles once they’re placed without leaving a hole that the robo-ants would pour out of, so choosing the right spots will be key.
就是把兩個緊急用 真空吸塵器的管嘴插入棲息地中, 在螞蟻脫身之前把它們吸光。 用力壓管嘴,就可以讓它 穿過棲息地前面的覆蓋薄膜, 進入棲息地中的任何一處。 任何經過的螞蟻 都會被吸起來並停止運作。 管嘴放好之後就無法再移動, 一移動就會留下一個洞 讓機器螞蟻逃出來, 所以關鍵是要選擇正確的插入點。
The habitat is made out of meter-long tubes. When the robots reach an intersection, they will pick randomly whether to go left, right, or forward. They only go backward if they hit hit another robo-ant or a dead end.
棲息地是用一公尺長的 管子做成的。 當機器螞蟻到了交叉口時, 它們會隨機選擇要 左轉、右轉,或直走。 會回轉的情況只有撞到 另一隻機器螞蟻或是碰到死路。
Unfortunately, there are hundreds of them inside the habitat, and if even one escapes, it’ll do a lot of damage.
不幸的是,在棲息地中 有數百隻螞蟻, 只要有一隻逃脫, 就會造成很大的傷害。 只剩下不到五分鐘,
With just less than five minutes remaining, where should you place the 2 vacuum nozzles to suck up all the robo-ants? Pause the video now if you want to figure it out for yourself. Answer in: 3 Answer in: 2 Answer in: 1
你應該要把這兩個真空 吸塵器的管嘴放在哪裡 才能把所有機器螞蟻都吸起來? 機器螞蟻在棲息地中到處跑,
With robo-ants ricocheting all over the habitat, it might seem impossible to stop them before they break free. But this situation is simpler than it seems. Here's why.
看起來似乎無法在它們 逃出去之前阻止它們。 但這個情況其實 比看起來的還容易解決。 原因如下。
Imagine just two robo-ants crawling toward each other. When they collide, they immediately reverse directions. And what would that sequence of events look like if they crawled past each other instead? It would look exactly the same before and after their collision, but with their positions swapped. This is true every time a pair of robo-ants meet. Because the identities of individual ants don’t matter, you just need to figure out where you should put the nozzles to capture any single ant walking without interruption for less than 5 minutes, starting from any point in the habitat.
想像只有兩隻機器螞蟻, 它們在爬向彼此。 當它們相撞時,它們 馬上就會轉向反方向。 如果它們改成是爬過彼此, 那一連串事件 看起來會是什麼樣子? 在它們相撞之前和之後 看起來會完全一樣, 但它們位置會互換。 每當有一對螞蟻相碰時都是如此。 因為每一隻螞蟻的 個別身分並不重要, 你只需要想出你要把管嘴放在哪裡 才能捕捉到每一隻螞蟻, 且每隻螞蟻都會從 棲息地的任何地方 開始不間斷地行走 不到五分鐘的時間。
That’s much easier to conceptualize and solve. Placing the nozzles at intersections where three or four tubes meet seems like your best bet since that’s where the robo-ants might otherwise change directions and miss your nozzles.
這樣就比較容易概念化和解題了。 把管嘴放在三或四根管子的交叉口 似乎是最有勝算的選擇, 因為若不放在那裡, 機器螞蟻可能會改變方向, 錯過你的管嘴。
There are only four intersections… which two should you pick?
只有四個交叉口…… 你會挑哪兩個?
The top right intersection has to be one of them. If it isn’t, an ant crawling down from this intersection toward the dead end would crawl for four minutes to get back to the intersection, and then go in any of three directions, walking for at least another minute. Once you’ve placed a nozzle in the top right, the only other choice that has a chance to work is the bottom left. To see that this works, imagine an ant anywhere else in the habitat. Worst case scenario, the ant would start right next to the vacuum nozzle, marching away from it. But in all those worst cases, the ant would march for at most 4 meters before being sucked up into the vacuum. No other choice of two intersection points is guaranteed to get all the robo-ants within five minutes.
一定得選右上的交叉口。 如果沒有選它,當一隻螞蟻 從這個交叉口向下爬, 到達死路之後, 就會花四分鐘爬回到這個交叉點, 接著往另外三個方向之一前進, 再走至少一分鐘。 當你把一隻管嘴放在右上之後, 唯一有可能的選擇就是左下角了。 若想知道它如何運作, 想像在棲息地中的任何 其他一處有一隻螞蟻。 最糟糕的狀況,這隻螞蟻 會從管嘴旁邊的點開始 朝遠離管嘴的方向爬。 但在所有最糟的情況下, 螞蟻最多只能爬四公尺 就會被吸到真空吸塵器中。 只有選這兩個交叉點, 才能保證在五分鐘內 抓到所有的機器螞蟻。
Having vacuumed them all up, you’ve averted a major crisis. Before you mess with robo-ants again, you’ll want to have a robo-anteater ready. And wouldn’t it be cool if it could fly and breathe fire? There’s no way that could go wrong!
把它們通通吸掉之後, 你阻止了一項重大危機。 在你下次要亂搞機器螞蟻之前, 你會想要把機器食蟻獸先準備好。 如果它還能飛行 和噴火,不是很酷嗎? 那不可能會出錯的!