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Add HE 2022 writeup
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‎hackyeaster_2022/README.md

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# Hacky Easter 2022
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## Level 1
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Welcome Flag<br/>
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## Level 2
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[Sp4c3 Inv4d3r5!](level_2/space_invaders/)<br/>
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[Glitch](level_2/glitch/)<br/>
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[I Key, You Key, ASCII](level_2/i_key_you_key_ascii/)<br/>
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[Alpha Bravo Charlie](level_2/alpha_bravo_charlie/)<br/>
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## Level 3
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[The Unicorn](level_3/the_unicorn/)<br/>
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‎hackyeaster_2022/level_2/alpha_bravo_charlie/README.md

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# Alpha Bravo Charlie
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## Description
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Level: noob<br/>
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Author: PS
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I received a strange message on my walkie-talkie today:
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```
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hotel echo two zero two two{papa hotel oscar november echo tango india charlie}
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```
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## Solution
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This one is pretty easy, simply take the first letter of every word (except for numbers) to get: `he2020{phonetic}`.
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‎hackyeaster_2022/level_2/glitch/README.md

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# Glitch
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## Description
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Level: noob<br/>
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Author: PS
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I got a flag, but it's glitched somehow.
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```
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}ɥɔʇᴉしƃ_ǝしʇʇᴉし_ɐ_ʇ己几ɾ{ᄅᄅ０ᄅǝɥ
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```
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## Solution
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The flag seems to be upside down. [This online tool](https://www.upsidedowntext.com/) can be used to flip text upside
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down and outputs:
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```
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he2０22}j几己t‾a‾しittしe‾gしitch{
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```
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From there we can guess the flag `he2022{just_a_little_glitch}`.
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‎hackyeaster_2022/level_2/i_key_you_key_ascii/README.md

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# I Key, You Key, ASCII
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## Description
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Level: noob<br/>
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Author: PS
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Look what I was drawing in my text editor!
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```
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.. .. .. 68 65 32 30 .. .. ..
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.. .. 32 ██ ██ ██ ██ 32 .. ..
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.. 7b ██ ██ ██ ██ ██ ██ 74 ..
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.. 68 ██ ██ ██ ██ ██ ██ 31 ..
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73 ██ ██ ██ ██ ██ ██ ██ ██ 5f
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30 ██ ██ ██ ██ ██ ██ ██ ██ 6e
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33 ██ ██ ██ ██ ██ ██ ██ ██ 5f
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31 ██ ██ ██ ██ ██ ██ ██ ██ 73
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5f ██ ██ ██ ██ ██ ██ ██ ██ 72
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33 ██ ██ ██ ██ ██ ██ ██ ██ 33
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33 ██ ██ ██ ██ ██ ██ ██ ██ 33
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.. 6c ██ ██ ██ ██ ██ ██ 79 ..
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.. 5f ██ ██ ██ ██ ██ ██ 73 ..
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.. .. 31 ██ ██ ██ ██ 6d .. ..
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.. .. .. 70 6c 33 7d .. .. ..
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```
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## Solution
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The challenge title says it all, simply remove the extra symbols and convert from hex to ascii.
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This can be done in [CyberChef](https://gchq.github.io/CyberChef/) by using two Find/Replace recipes as well as a From
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Hex one: [Cyber Chef with
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recipes](https://gchq.github.io/CyberChef/#recipe=Find_/_Replace(%7B'option':'Regex','string':'%E2%96%88%E2%96%88'%7D,'',true,false,true,false)Find_/_Replace(%7B'option':'Simple%20string','string':'..'%7D,'',true,false,true,false)From_Hex('Auto')&input=Li4gLi4gLi4gNjggNjUgMzIgMzAgLi4gLi4gLi4gIAouLiAuLiAzMiDilojilogg4paI4paIIOKWiOKWiCDilojiloggMzIgLi4gLi4gIAouLiA3YiDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCA3NCAuLiAgCi4uIDY4IOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIDMxIC4uICAKNzMg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCA1ZiAgCjMwIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojiloggNmUgIAozMyDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIDVmICAKMzEg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCA3MyAgCjVmIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojiloggNzIgIAozMyDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIDMzICAKMzMg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCAzMyAgCi4uIDZjIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIDc5IC4uICAKLi4gNWYg4paI4paIIOKWiOKWiCDilojilogg4paI4paIIOKWiOKWiCDilojiloggNzMgLi4gIAouLiAuLiAzMSDilojilogg4paI4paIIOKWiOKWiCDilojiloggNmQgLi4gLi4gIAouLiAuLiAuLiA3MCA2YyAzMyA3ZCAuLiAuLiAuLiAg).
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This directly gives the flag `he2022{th1s_0n3_1s_r3333ly_s1mpl3}`.
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‎hackyeaster_2022/level_2/space_invaders/README.md

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# Sp4c3 Inv4d3r5!
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## Description
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Level: noob<br/>
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Author: PS
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My favourite game in the 80s was Space Invaders!
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[spaceinvaders.pdf](spaceinvaders.pdf)
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## Solution
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Simply call `pdftotext spaceinvards.pdf` and `cat spaceinvaders.txt` to get:
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```
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he20
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22{I nv4d 3rs_
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fr0m _sp4 c3!}
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```
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Then reassemble the flag `he2022{Inv4d3rs_fr0m_sp4c3!}`.

‎hackyeaster_2022/level_2/space_invaders/spaceinvaders.pdf

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‎hackyeaster_2022/level_3/city_trip/README.md

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# City Trip
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## Description
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Level: easy<br/>
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Author: PS
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I made a nice city trip. Find out where I was!
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🚩 Flag
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- street's name in lowercase and without spaces
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- district or city name is not enough, we need the street
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- example: Main Rd -> he2022{mainrd}
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![](citytrip.jpg)
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## Solution
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For this challenge we are given an image and have to find its location. Probably the best method to do so, is to use
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Google Image search. This directly leads us to "The Five Points" in Manhatten, a location close to the road in question.
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We can then use Google Street View to search for the exact location.
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‎hackyeaster_2022/level_3/city_trip/citytrip.jpg

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‎hackyeaster_2022/level_3/fibonacci_rabbits/README.md

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# Fibonacci Rabbits
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## Description
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Level: easy<br/>
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Author: PS
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Everyone loves rabbits!
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http://46.101.107.117:2201
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## Solution
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For this challenge we are given a website that contains several images of rabbits:
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![](rabbits.png)
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Upon closer inspection, we can see that the images contain fibonacci numbers as a suffix:
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```html
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<div><img src="images/rabbit-17711.jpg" /><a href="#">Petal</a></div>
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<div><img src="images/rabbit-75025.jpg" /><a href="#">Harley</a></div>
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<div><img src="images/rabbit-34.jpg" /><a href="#">Rosie</a></div>
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<div><img src="images/rabbit-987.jpg" /><a href="#">Petunia</a></div>
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<div><img src="images/rabbit-8.jpg" /><a href="#">Mortimer</a></div>
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<div><img src="images/rabbit-1.jpg" /><a href="#">Henry</a></div>
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<div><img src="images/rabbit-144.jpg" /><a href="#">Miffy</a></div>
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<div><img src="images/rabbit-2584.jpg" /><a href="#">E.B.</a></div>
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<div><img src="images/rabbit-89.jpg" /><a href="#">Baxter</a></div>
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<div><img src="images/rabbit-55.jpg" /><a href="#">Archie</a></div>
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<div><img src="images/rabbit-5.jpg" /><a href="#">Murphy</a></div>
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<div><img src="images/rabbit-317811.jpg" /><a href="#">Doc</a></div>
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<div><img src="images/rabbit-2.jpg" /><a href="#">Hopper</a></div>
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<div><img src="images/rabbit-6765.jpg" /><a href="#">Fluffy</a></div>
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<div><img src="images/rabbit-46368.jpg" /><a href="#">Daffodil</a></div>
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<div><img src="images/rabbit-28657.jpg" /><a href="#">Buttons</a></div>
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<div><img src="images/rabbit-233.jpg" /><a href="#">Freddie</a></div>
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<div><img src="images/rabbit-1597.jpg" /><a href="#">Roger</a></div>
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<div><img src="images/rabbit-514229.jpg" /><a href="#">Bucky</a></div>
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<div><img src="images/rabbit-4181.jpg" /><a href="#">Oliver</a></div>
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<div><img src="images/rabbit-13.jpg" /><a href="#">Olive</a></div>
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<div><img src="images/rabbit-3.jpg" /><a href="#">Bugs</a></div>
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<div><img src="images/rabbit-377.jpg" /><a href="#">Flower</a></div>
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<div><img src="images/rabbit-10946.jpg" /><a href="#">Chester</a></div>
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<div><img src="images/rabbit-610.jpg" /><a href="#">Bubbles</a></div>
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<div><img src="images/rabbit-121393.jpg" /><a href="#">Coco</a></div>
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<div><img src="images/rabbit-21.jpg" /><a href="#">Clover</a></div>
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```
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Stripping the unnecessary HTML stuff and ordering them by number we get:
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```
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1
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2
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3
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5
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8
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13
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21
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34
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55
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89
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144
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233
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377
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610
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987
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1597
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2584
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4181
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6765
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10946
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17711
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28657
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46368
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75025
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121393
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317811
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514229
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```
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Note that the 27th fibonacci number is missing, so that rabbit must be hiding something.
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We can simply visit `images/rabbit-196418.jpg` to get the flag:
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![](cat.jpg)
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‎hackyeaster_2022/level_3/fibonacci_rabbits/cat.jpg

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