[Script Info]
Title: 
[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
Dialogue: 0,0:00:07.23,0:00:10.09,Default,,0000,0000,0000,,As a wildfire rages through\Nthe grasslands,
Dialogue: 0,0:00:10.09,0:00:14.60,Default,,0000,0000,0000,,three lions and three wildebeest\Nflee for their lives.
Dialogue: 0,0:00:14.60,0:00:16.12,Default,,0000,0000,0000,,To escape the inferno,
Dialogue: 0,0:00:16.12,0:00:21.22,Default,,0000,0000,0000,,the must cross over to the left bank\Nof a crocodile-infested river.
Dialogue: 0,0:00:21.22,0:00:24.31,Default,,0000,0000,0000,,Fortunately, there happens\Nto be a raft nearby.
Dialogue: 0,0:00:24.31,0:00:27.49,Default,,0000,0000,0000,,It can carry up to two animals at a time,
Dialogue: 0,0:00:27.49,0:00:30.100,Default,,0000,0000,0000,,and needs as least one lion\Nor wildebeest on board
Dialogue: 0,0:00:30.100,0:00:33.35,Default,,0000,0000,0000,,to row it across the river.
Dialogue: 0,0:00:33.35,0:00:35.67,Default,,0000,0000,0000,,There's just one problem.
Dialogue: 0,0:00:35.67,0:00:39.81,Default,,0000,0000,0000,,If the lions every outnumber the\Nwildebeest on either side of the river,
Dialogue: 0,0:00:39.81,0:00:41.44,Default,,0000,0000,0000,,even for a moment,
Dialogue: 0,0:00:41.44,0:00:45.43,Default,,0000,0000,0000,,their instincts will kick in,\Nand the results won't be pretty.
Dialogue: 0,0:00:45.43,0:00:50.08,Default,,0000,0000,0000,,That includes the animals in the boat\Nwhen its on a given side of the river.
Dialogue: 0,0:00:50.08,0:00:54.26,Default,,0000,0000,0000,,What's the fast way for all six animals\Nto get across
Dialogue: 0,0:00:54.26,0:00:57.97,Default,,0000,0000,0000,,without the lions stopping for dinner?
Dialogue: 0,0:00:57.97,0:01:01.56,Default,,0000,0000,0000,,Pause here if you want \Nto figure it out for yourself.
Dialogue: 0,0:01:01.56,0:01:02.82,Default,,0000,0000,0000,,Answer in: 3
Dialogue: 0,0:01:02.82,0:01:03.84,Default,,0000,0000,0000,,Answer in: 2
Dialogue: 0,0:01:03.84,0:01:04.80,Default,,0000,0000,0000,,Answer in: 1
Dialogue: 0,0:01:04.80,0:01:06.91,Default,,0000,0000,0000,,If you feel stuck on a problem like this,
Dialogue: 0,0:01:06.91,0:01:10.82,Default,,0000,0000,0000,,try listing all the decisions you can make\Nat each point,
Dialogue: 0,0:01:10.82,0:01:14.20,Default,,0000,0000,0000,,and the consequences each choice\Nleads to.
Dialogue: 0,0:01:14.20,0:01:18.01,Default,,0000,0000,0000,,For instance, there are five options\Nfor who goes across first:
Dialogue: 0,0:01:18.01,0:01:19.19,Default,,0000,0000,0000,,one wildebeest
Dialogue: 0,0:01:19.19,0:01:20.19,Default,,0000,0000,0000,,one lion.
Dialogue: 0,0:01:20.19,0:01:21.29,Default,,0000,0000,0000,,two wildebeest,
Dialogue: 0,0:01:21.29,0:01:22.28,Default,,0000,0000,0000,,two lions,
Dialogue: 0,0:01:22.28,0:01:23.74,Default,,0000,0000,0000,,or one of each.
Dialogue: 0,0:01:23.74,0:01:25.24,Default,,0000,0000,0000,,If one animal goes alone,
Dialogue: 0,0:01:25.24,0:01:27.59,Default,,0000,0000,0000,,it will just have to come straight back.
Dialogue: 0,0:01:27.59,0:01:29.48,Default,,0000,0000,0000,,And if two wildebeest cross first,
Dialogue: 0,0:01:29.48,0:01:32.46,Default,,0000,0000,0000,,the remaining one will immediately\Nget eaten.
Dialogue: 0,0:01:32.46,0:01:34.98,Default,,0000,0000,0000,,So those options are all out.
Dialogue: 0,0:01:34.98,0:01:36.60,Default,,0000,0000,0000,,Sending two lions,
Dialogue: 0,0:01:36.60,0:01:38.27,Default,,0000,0000,0000,,or one of each animal,
Dialogue: 0,0:01:38.27,0:01:42.51,Default,,0000,0000,0000,,can actually both lead to solutions\Nin the same number of moves.
Dialogue: 0,0:01:42.51,0:01:45.67,Default,,0000,0000,0000,,For the sake of time,\Nwe'll focus on the second one.
Dialogue: 0,0:01:45.67,0:01:47.64,Default,,0000,0000,0000,,One of each animal crosses.
Dialogue: 0,0:01:47.64,0:01:51.08,Default,,0000,0000,0000,,Now, if the wildebeest stays \Nand the lion returns,
Dialogue: 0,0:01:51.08,0:01:53.54,Default,,0000,0000,0000,,there will be three lions\Non the right bank.
Dialogue: 0,0:01:53.54,0:01:56.46,Default,,0000,0000,0000,,Bad news for the two remaining wildebeest.
Dialogue: 0,0:01:56.46,0:01:59.25,Default,,0000,0000,0000,,So we need to have the lion\Nstay on the left bank
Dialogue: 0,0:01:59.25,0:02:01.94,Default,,0000,0000,0000,,and the wildebeest go back to the right.
Dialogue: 0,0:02:01.94,0:02:03.99,Default,,0000,0000,0000,,Now we have the same five options,
Dialogue: 0,0:02:03.99,0:02:07.14,Default,,0000,0000,0000,,but with one lion \Nalready on the left bank.
Dialogue: 0,0:02:07.14,0:02:10.30,Default,,0000,0000,0000,,If two wildebeest go,\Nthe one that stays will get eaten,
Dialogue: 0,0:02:10.30,0:02:12.42,Default,,0000,0000,0000,,and if one of each animal goes,
Dialogue: 0,0:02:12.42,0:02:14.98,Default,,0000,0000,0000,,the wildebeest on the raft\Nwill be outnumbered
Dialogue: 0,0:02:14.98,0:02:17.73,Default,,0000,0000,0000,,as soon as it reached the otherside.
Dialogue: 0,0:02:17.73,0:02:19.08,Default,,0000,0000,0000,,So that's a dead end,
Dialogue: 0,0:02:19.08,0:02:20.98,Default,,0000,0000,0000,,which means that at the third crossing,
Dialogue: 0,0:02:20.98,0:02:23.65,Default,,0000,0000,0000,,only the two lions can go.
Dialogue: 0,0:02:23.65,0:02:25.07,Default,,0000,0000,0000,,One gets dropped off,
Dialogue: 0,0:02:25.07,0:02:27.46,Default,,0000,0000,0000,,leaving two lions on the left bank.
Dialogue: 0,0:02:27.46,0:02:30.46,Default,,0000,0000,0000,,The third lion takes the raft back to\Nthe right bank
Dialogue: 0,0:02:30.46,0:02:33.02,Default,,0000,0000,0000,,where the wildebeest are waiting.
Dialogue: 0,0:02:33.02,0:02:34.24,Default,,0000,0000,0000,,What now?
Dialogue: 0,0:02:34.24,0:02:37.30,Default,,0000,0000,0000,,Well, since we've got two lions waiting\Non the left bank,
Dialogue: 0,0:02:37.30,0:02:40.88,Default,,0000,0000,0000,,the only option is for two wildebeest\Nto cross.
Dialogue: 0,0:02:40.88,0:02:44.77,Default,,0000,0000,0000,,Next, there's no sense in two wildebeest\Ngoing back,
Dialogue: 0,0:02:44.77,0:02:47.34,Default,,0000,0000,0000,,since that just reverses the last step.
Dialogue: 0,0:02:47.34,0:02:48.91,Default,,0000,0000,0000,,And if two lions go back,
Dialogue: 0,0:02:48.91,0:02:51.92,Default,,0000,0000,0000,,they'll outnumber the wildebeest\Non the right bank.
Dialogue: 0,0:02:51.92,0:02:55.75,Default,,0000,0000,0000,,So one lion and one wildebeest\Ntake the raft back
Dialogue: 0,0:02:55.75,0:02:58.80,Default,,0000,0000,0000,,leaving us with one of each animal\Non the left bank
Dialogue: 0,0:02:58.80,0:03:00.96,Default,,0000,0000,0000,,and two of each on the right.
Dialogue: 0,0:03:00.96,0:03:05.15,Default,,0000,0000,0000,,Again, there's no point in sending \Nthe lion-wildebeest pair back,
Dialogue: 0,0:03:05.15,0:03:07.98,Default,,0000,0000,0000,,so the next trip should be either\Na pair of lions
Dialogue: 0,0:03:07.98,0:03:10.10,Default,,0000,0000,0000,,or a pair of wildebeest.
Dialogue: 0,0:03:10.10,0:03:13.89,Default,,0000,0000,0000,,If the lions go, they'd eat the wildebeest\Non the left, so they stay,
Dialogue: 0,0:03:13.89,0:03:16.76,Default,,0000,0000,0000,,and the two wildebeest cross instead.
Dialogue: 0,0:03:16.76,0:03:20.84,Default,,0000,0000,0000,,Now we're quite close because the\Nwildebeest are all where they need to be
Dialogue: 0,0:03:20.84,0:03:22.77,Default,,0000,0000,0000,,with safety in numbers.
Dialogue: 0,0:03:22.77,0:03:25.68,Default,,0000,0000,0000,,All that's left is for that one lion\Nto raft back
Dialogue: 0,0:03:25.68,0:03:29.39,Default,,0000,0000,0000,,and bring his fellow lions over\None by one.
Dialogue: 0,0:03:29.39,0:03:31.59,Default,,0000,0000,0000,,That makes eleven trips total,
Dialogue: 0,0:03:31.59,0:03:35.46,Default,,0000,0000,0000,,the smallest number needed\Nto get everyone across safely.
Dialogue: 0,0:03:35.46,0:03:40.06,Default,,0000,0000,0000,,The solution that involves sending both\Nlions on the first step works similarly,
Dialogue: 0,0:03:40.06,0:03:43.62,Default,,0000,0000,0000,,and also takes eleven crossings.
Dialogue: 0,0:03:43.62,0:03:47.33,Default,,0000,0000,0000,,The six animals escape unharmed\Nfrom the fire just in time
Dialogue: 0,0:03:47.33,0:03:50.25,Default,,0000,0000,0000,,and begin their new lives \Nacross the river.
Dialogue: 0,0:03:50.25,0:03:52.68,Default,,0000,0000,0000,,Of course, now that the danger's passed,
Dialogue: 0,0:03:52.68,0:03:57.12,Default,,0000,0000,0000,,it remains to be see how long their\Nunlikely alliance will last.