[{"data":1,"prerenderedAt":350},["ShallowReactive",2],{"project-10476716":3},{"id":4,"name":5,"line":6,"line_source":7,"title":8,"url":9,"domain":10,"maker":11,"posted_at":12,"year":13,"points":14,"comments":15,"rank_in_year":16,"shown_in_year":17,"top":18,"tier":19,"category":20,"subcategory":21,"format":22,"keywords":23,"reception":27,"sentiment":28,"stance_mix":29,"scored_comments":33,"aspects":34,"strip":42,"post_text":43,"what":44,"said":66,"maker_in_thread":151,"shape":159,"grid":164,"attempts":309,"same_week":314,"maker_shows":280,"maker_hidden":342,"reader_version":343,"card":344},"10476716","Parachuting robots","a programming puzzle","title","Show HN: Parachuting robots – a programming puzzle","http:\u002F\u002Fdavid-peter.de\u002Fparachuting-robots\u002F","david-peter.de","sharkdp",1446194380,2015,60,55,469,2565,19,"notable","learning_science","programming puzzle","web_app",[21,24,25,26],"robot simulation","linked list cycle detection","assembly-like language","curious",0.068,{"positive":30,"neutral":31,"mixed":32,"critical":30},5,25,3,38,{"idea":35,"performance":37,"design":39,"execution":41},{"positive":32,"critical":36},2,{"positive":38,"critical":38},0,{"positive":40,"critical":38},1,{"positive":38,"critical":32},[32,40,40,32,38,32,32,32,38,32,32,38,30,32,32,32,38,38,30,32,30,32,32,32,32,38,32,38,32,32,38,32,40,40,32,32,32,32,32,30],null,{"problem":45,"audience":43,"pricing":43,"motivation":43,"time_to_build":43,"stack":57,"openness":65,"stage":65,"team_size":65},{"value":46,"source":47,"evidence":48},"Solve a puzzle where two robots move on an infinite line so one catches the other's parachute.","commenter",[49,53],{"id":50,"by":51,"text":52},"10477210","moftz","Here's my best implementation: ``` start: left skipNext goto start fast: left goto fast ``` Red and Blue must take three cycles to move one space until Blue hits Red's parachute.…",{"id":54,"by":55,"text":56},"10477513","sireat","I kept thinking,how would robots know when to switch directions? That is when I realized that robots do not have to crash head on but overtaking is sufficient. This is one case…",[58],{"value":59,"source":47,"evidence":60},"JavaScript",[61],{"id":62,"by":63,"text":64},"10480495","jack9","slow: left skipNext goto slow fast: left left left left left left left left left left left left left left left left left left left left left left left left left left left left…","unknown",{"praise":67,"objections":94,"requests":113,"questions":127,"alternatives":135},[68,83],{"value":69,"source":47,"evidence":70},"Fun puzzle with a great visualization",[71,75,79],{"id":72,"by":73,"text":74},"10476988","Lewton","I'm not sure I would have gotten the puzzle without the great visualization. Very cool! Much appreciated entertainment on a lazy friday at work :)",{"id":76,"by":77,"text":78},"10477368","somehnreader","Fantastic puzzle. Took me ages to realise the twist though, because I was somehow set on making them oscillate further on every iteration and couldn't understand how I was to…",{"id":80,"by":81,"text":82},"10477233","Geee","Great puzzle, took me some time to get it.",{"value":84,"source":47,"evidence":85},"Nicely created site",[86,90],{"id":87,"by":88,"text":89},"10477057","kanche","I made it through with two [0] [0] https:\u002F\u002Fgist.github.com\u002Fkanche\u002F92c92c5e926ebc66da68 To watch them run around is so cool! Cool puzzle. Nicely created site. I am trying to give…",{"id":91,"by":92,"text":93},"10476897","trymas","Wow, great puzzle. Also great implementation and beautiful site. Though, IMHO there could be a button named \"parse & run\", my eyes have missed a \"parse\" button, and I thought…",[95,102],{"value":96,"source":47,"evidence":97},"Play button disabled before parsing is confusing; parse and run needed",[98,99],{"id":91,"by":92,"text":93},{"id":100,"by":92,"text":101},"10476993","Answering your question, maybe a popover with text \"Your program is not parsed\" would help? Also somehow I am used to \"build\" (instead of \"parse\") terminology, so my eyes just…",{"value":103,"source":47,"evidence":104},"Randomize routine makes some solutions fail",[105,109],{"id":106,"by":107,"text":108},"10477281","lucb1e","With your code they end up right where they started? I see 'random locations' in the text above but the location is always the same here. Adding a couple of 'left's works,…",{"id":110,"by":111,"text":112},"10477412","pbhjpbhj","I think they meant: ``` left x 6 # but that should probably be 7? as maxRange in the randomize routine is 8. scan: skipNext right goto scan ``` Which works but only because the…",[114,121],{"value":115,"source":47,"evidence":116},"Ability to share code",[117],{"id":118,"by":119,"text":120},"10476930","rplnt","How many labels you need to solve this? I have four, but I wonder if it can be simplified. Suggestion: Add ability to share the code.",{"value":122,"source":47,"evidence":123},"Grading of code by efficiency",[124],{"id":125,"by":107,"text":126},"10477316","Additional suggestion: ability to grade code. I see solutions that are a lot shorter than mine in code (2 labels, 5 instructions), but they take about 87 instruction cycles to…",[128],{"value":129,"source":47,"evidence":130},"Whether goal is short or fast program",[131],{"id":132,"by":133,"text":134},"10477080","progx","Is the goal to create a short programm (less lines) or an efficient programm (fast)? Spoiler! ``` start: left skipNext goto start speedup: left goto speedup ```",[136],{"value":137,"source":47,"evidence":138},"Microsoft interview question on loop detection in linked lists",[139,143,147],{"id":140,"by":141,"text":142},"10477318","nyan4","\"It seems to originate from a Microsoft interview question.\" Using inefficiency to solve problems, I'm not surprised.",{"id":144,"by":145,"text":146},"10478513","iconjack","This problem was posed to me for real in a Microsoft interview in the late 90s. At first I was like \"How hard could this be?\" but quickly discovered that it wasn't so obvious. If…",{"id":148,"by":149,"text":150},"10477109","sugarcube","That interview question seems related to the \"how to detect loops in a potentially infinite list\" question which I was asked at least once.",{"comments":36,"answered":40,"key":152},[153,156],{"id":154,"text":155},"10476974","Thank you, I'm glad you liked it! I see, the disabled play button in the beginning is not optimal. Replacing \"parse\" with \"parse & run\" is an interesting option. I'm not sure…",{"id":157,"text":158},"10477138","Great suggestion, thanks! I added (state-dependent) mouse-over tooltips for all buttons.",{"commenters":160,"max_depth":161,"maker_replies":36,"first_comment_mins":162,"lifespan_hours":163},39,6,64,254,[165,167,169,172,173,176,179,182,184,186,188,190,191,192,193,197,199,202,205,208,211,214,216,218,220,223,224,228,231,235,238,242,245,247,250,252,254,256,259,262,264,265,268,271,275,277,278,282,285,289,292,297,301,304,307],[50,38,32,166,51,38],"project\u002Fneutral\u002Fidea",[140,38,40,168,141,38],"project\u002Fcritical\u002Fidea",[170,38,40,168,171,38],"10477475","nothis",[144,38,32,166,145,38],[174,38,32,166,175,38],"10477486","verroq",[177,38,38,178,88,38],"10477597","commenter\u002Fneutral\u002Fexecution",[180,38,32,166,181,38],"10477654","Fiahil",[62,38,32,183,63,38],"project\u002Fneutral\u002Fperformance",[91,40,32,185,92,38],"project\u002Fmixed\u002Fdesign",[154,40,38,187,11,40],"maker\u002Fneutral\u002Fdesign",[100,40,32,189,92,38],"project\u002Fneutral\u002Fdesign",[157,40,38,187,11,40],[132,36,32,166,133,38],[148,32,32,166,149,38],[194,32,38,195,196,38],"10477307","commenter\u002Fneutral\u002Fnone","andrelaszlo",[198,32,38,195,149,38],"10499405",[54,200,30,201,55,38],4,"project\u002Fpositive\u002Fidea",[203,200,32,166,204,38],"10477614","fouadf",[206,200,32,166,207,38],"10477707","chki",[209,200,32,166,210,38],"10477713","typicalbender",[212,30,32,166,213,38],"10476986","samsaga2",[215,30,38,178,73,38],"10476990",[217,30,38,178,213,38],"10477013",[219,30,38,178,73,38],"10477019",[221,30,38,178,222,38],"10477164","esolyt",[76,161,30,201,77,38],[225,226,32,166,227,38],"10477092",7,"citeguised",[72,229,30,230,73,38],8,"project\u002Fpositive\u002Fdesign",[232,233,32,166,234,38],"10477589",9,"Beltiras",[236,233,38,178,237,38],"10479735","jonsen",[239,240,32,183,241,38],"10477724",10,"meshko",[243,240,38,244,237,38],"10479623","commenter\u002Fneutral\u002Fperformance",[118,246,32,166,119,38],11,[248,246,32,166,249,38],"10476936","alexmic",[251,246,38,195,119,38],"10477035",[253,246,38,195,73,38],"10477324",[255,246,32,166,119,38],"10477370",[257,246,38,258,73,38],"10477540","commenter\u002Fpositive\u002Fnone",[260,246,32,166,261,38],"10476939","jmcannon",[87,246,32,263,88,38],"project\u002Fmixed\u002Fidea",[125,246,32,166,107,38],[266,246,38,267,73,38],"10477330","commenter\u002Fcritical\u002Fidea",[269,246,38,270,107,38],"10477336","commenter\u002Fneutral\u002Fidea",[272,273,32,166,274,38],"10477201",12,"zuck9",[106,273,40,276,107,38],"project\u002Fcritical\u002Fexecution",[110,273,40,276,111,38],[279,280,32,166,281,38],"10477291",13,"bvenkysubbu",[283,280,38,195,284,38],"10477337","odabaxok",[286,287,32,166,288,38],"10479853",14,"vk0",[290,287,32,263,291,38],"10480601","drewm1980",[293,294,30,295,296,38],"10536235",15,"project\u002Fpositive\u002Fnone","JacobTuttle",[298,299,40,276,300,38],"10478443",16,"vinody",[302,303,32,166,234,38],"10477618",17,[305,303,32,166,306,38],"10478346","symmetricsaurus",[80,308,30,201,81,38],18,[310,313],{"id":311,"t":312,"points":40,"comments":38},"10464572",1446041991,{"id":4,"t":12,"points":14,"comments":15},[315,320,324,329,334,338],{"id":316,"name":317,"points":318,"category":319},"10477721","Twitch Installs Arch Linux",802,"games",{"id":321,"name":322,"points":323,"category":20},"10499683","React for Beginners",178,{"id":325,"name":326,"points":327,"category":328},"10476696","Vertexshaderart.com",145,"creative",{"id":330,"name":331,"points":332,"category":333},"10493891","WOPR",125,"dev_tools",{"id":335,"name":336,"points":337,"category":333},"10509077","Administrate",124,{"id":339,"name":340,"points":341,"category":20},"10472153","Code4Startup",113,false,"v2",{"id":345,"name":5,"line":6,"ai":342,"cat":20,"year":13,"points":14,"comments":15,"rec":27,"s":346,"top":18,"kw":347,"maker":11,"domain":10,"tier":19,"attempts":36,"strip":348,"url":9,"mix":349,"praise":69,"objection":96,"sub":21},10476716,0.07,[21,24,25,26],"3113033303305333005353333030330311333335",[30,31,32,30],1794036537196]