[{"data":1,"prerenderedAt":417},["ShallowReactive",2],{"project-7201405":3},{"id":4,"name":5,"line":5,"line_source":6,"title":7,"url":8,"domain":9,"maker":10,"posted_at":11,"year":12,"points":13,"comments":14,"rank_in_year":15,"shown_in_year":16,"top":17,"tier":18,"category":19,"subcategory":20,"format":21,"keywords":22,"reception":27,"sentiment":28,"stance_mix":29,"scored_comments":34,"aspects":35,"strip":47,"post_text":49,"what":50,"said":76,"maker_in_thread":173,"shape":185,"grid":189,"attempts":356,"same_week":378,"maker_shows":30,"maker_hidden":409,"reader_version":410,"card":411},"7201405","Speedsums","title","Show HN: Speedsums","http:\u002F\u002Fwww.speedsums.com","speedsums.com","refrigerator",1391873720,2014,64,62,493,2272,22,"notable","learning_science","mental arithmetic practice","web_app",[23,24,25,26],"mental math","speed arithmetic","times tables","practice game","roasted",-0.374,{"positive":30,"neutral":31,"mixed":32,"critical":33},6,13,0,21,40,{"design":36,"idea":39,"privacy":41,"docs":44,"execution":45,"performance":46},{"positive":37,"critical":38},3,10,{"positive":40,"critical":32},2,{"positive":42,"critical":43},1,9,{"positive":32,"critical":32},{"positive":32,"critical":40},{"positive":32,"critical":32},[48,42,42,48,42,42,37,42,32,32,32,37,37,42,42,42,42,37,48,32,42,48,37,37,32,42,48,37,42,42,42,42,42,37,42,42,42,37,37,42],5,null,{"problem":51,"audience":49,"pricing":49,"motivation":49,"time_to_build":49,"stack":63,"openness":74,"stage":75,"team_size":74},{"value":52,"source":53,"evidence":54},"Practising quick mental sums and multiplication","inferred",[55,59],{"id":56,"by":57,"text":58},"7201818","Houshalter","I wonder if teaching people analog math would be better. This is more practical if you don't need exact quantities, and more in line with how your brain actually works. Symbolic…",{"id":60,"by":61,"text":62},"7201762","idiot900","FWIW I thought the insults were pretty funny. They put into context the uselessness of learning to multiply and divide marginally more quickly.",[64],{"value":65,"source":53,"evidence":66},"JavaScript",[67,71],{"id":68,"by":69,"text":70},"7201806","kaahne","Cool little Game ! As a lot of people here, I threw together some JS to try and 'hack' the challenge. As mentioned by OP, this is \"staggeringly\" easy to do. Yet, I was wondering…",{"id":72,"by":10,"text":73},"7201408","It's staggeringly easy to hack because it's a fully client-side app but that's not really the point :)","unknown","launched",{"praise":77,"objections":98,"requests":138,"questions":153,"alternatives":158},[78,91],{"value":79,"source":80,"evidence":81},"Insult copy is funny and refreshing","commenter",[82,86,87],{"id":83,"by":84,"text":85},"7201884","callum85","The 'motivational' comments were hilarious and refreshing. I strongly disagree with the other advice you've been given here. Don't 'turn it up to 11' to remove all the subtlety…",{"id":60,"by":61,"text":62},{"id":88,"by":89,"text":90},"7201726","ppod","I liked it, it made me smile. The standard \"have-an-amazing-day\" tone of sites submitted here is grating after a while.",{"value":92,"source":80,"evidence":93},"Good for practising typing numbers",[94],{"id":95,"by":96,"text":97},"7202677","peter_l_downs","This a great way to improve your touch-typing skills. I'm extremely accurate on letters and the couple of symbols that I tend to use in programming, but straight numbers are the…",[99,114,124,131],{"value":100,"source":80,"evidence":101},"Insulting copy is user hostile",[102,106,110],{"id":103,"by":104,"text":105},"7201550","iandanforth","I think this kind of practice is great. However I don't think insulting learners is ever a good idea. \"If you got below like 30 on your first attempt, you should probably…",{"id":107,"by":108,"text":109},"7201547","poopicus","This is incredibly user hostile with lines like \"you should probably practice a little before embarrassing yourself again\" and \"It should not take 4.18s to solve that next time.\"…",{"id":111,"by":112,"text":113},"7201615","henryaj","Agreed - I was quite taken aback by this. Not exactly beginner-friendly...",{"value":115,"source":80,"evidence":116},"Client-side app is easy to cheat",[117,118,121],{"id":72,"by":10,"text":73},{"id":119,"by":10,"text":120},"7201575","like I said, staggeringly easy to hack...",{"id":122,"by":10,"text":123},"7201670","like I said, it's staggeringly easy to hack because it's a client side app!",{"value":125,"source":80,"evidence":126},"Division and addition signs look alike",[127],{"id":128,"by":129,"text":130},"7201540","webbedhands","Sometimes it's hard to differentiate between the addition and the division sign. That's rather annoying.",{"value":132,"source":80,"evidence":133},"No number pad makes it slow",[134],{"id":135,"by":136,"text":137},"7201756","memming","Only if I had a keypad! Typing numbers in a mini keyboard is so slow.",[139,146],{"value":140,"source":80,"evidence":141},"Server-side scoring to prevent cheating",[142],{"id":143,"by":144,"text":145},"7202228","asadlionpk","keeping questions captcha-like and calculating the score on server side, is one solution.",{"value":147,"source":80,"evidence":148},"Sanitize leaderboard usernames",[149],{"id":150,"by":151,"text":152},"7202516","fudgekludge","Just wanted to say that you should sanitize the leader board. Some of those usernames completely turn me off from the concept.",[154],{"value":155,"source":80,"evidence":156},"How to prevent cheating in a client-side app",[157],{"id":68,"by":69,"text":70},[159,166],{"value":160,"source":80,"evidence":161},"Case Interview Math",[162],{"id":163,"by":164,"text":165},"7202163","bbx","This reminds me of Case Interview Math: https:\u002F\u002Fwww.caseinterview.com\u002Fmath\u002Fhome.php Try with \"Estimation Math\", \"Random\", and \"Hard\". A friend of mine told me about this website.…",{"value":167,"source":80,"evidence":168},"Eyeballing game",[169],{"id":170,"by":171,"text":172},"7202465","to3m","This sounds a little bit like the sort of stuff `the eyeballing game' makes you do: http:\u002F\u002Fwoodgears.ca\u002Feyeball\u002Findex.html",{"comments":174,"answered":40,"key":175},11,[176,179,182],{"id":177,"text":178},"7201557","I thought it would motivate people to try harder, but I guess it's backfiring... sorry! I'll change it",{"id":180,"text":181},"7201797","Yeah I do see what you mean, I should have either gone the whole hog or not at all, I actually read that book a couple of years ago as it turns out!",{"id":183,"text":184},"7201835","that's actually a really cool idea!",{"commenters":186,"max_depth":187,"maker_replies":174,"first_comment_mins":42,"lifespan_hours":188},47,4,15,[190,192,194,196,199,200,201,204,207,208,212,213,215,217,219,223,226,228,230,233,234,235,237,242,245,248,250,253,255,258,261,264,268,269,273,277,280,283,286,290,292,295,298,300,302,304,308,309,312,316,319,320,323,326,330,331,335,338,343,345,348,352],[83,32,48,191,84,32],"project\u002Fpositive\u002Fdesign",[103,42,42,193,104,32],"project\u002Fcritical\u002Fdesign",[177,42,32,195,10,42],"maker\u002Fneutral\u002Fdesign",[197,42,42,193,198,32],"7201684","GuiA",[180,42,32,195,10,42],[88,42,48,191,89,32],[202,42,42,193,203,32],"7201826","spiralganglion",[205,42,37,206,171,32],"7202442","project\u002Fneutral\u002Fdesign",[111,42,42,193,112,32],[209,42,37,210,211,32],"7202938","project\u002Fneutral\u002Fnone","3pt14159",[107,40,42,193,108,32],[56,37,37,214,57,32],"project\u002Fneutral\u002Fidea",[183,37,32,216,10,42],"maker\u002Fpositive\u002Fidea",[170,37,32,218,171,32],"other\u002Fneutral\u002Fidea",[220,187,32,221,222,32],"7201487","other\u002Fneutral\u002Fnone","lucb1e",[224,187,32,221,225,32],"7201692","orbitur",[227,187,32,221,222,32],"7202607",[68,48,37,229,69,32],"project\u002Fneutral\u002Fprivacy",[231,48,32,232,10,42],"7201836","maker\u002Fneutral\u002Fprivacy",[143,48,37,229,144,32],[128,30,42,193,129,32],[236,30,32,195,10,42],"7201576",[238,239,42,240,241,32],"7202108",7,"project\u002Fcritical\u002Fprivacy","beepp",[243,239,42,240,244,32],"7202162","wreegab",[246,239,42,240,247,32],"7202604","zjonsson",[72,249,32,232,10,42],8,[251,43,37,214,252,32],"7201666","agumonkey",[163,38,48,254,164,32],"project\u002Fpositive\u002Fidea",[256,174,32,221,257,32],"7201718","3825",[259,174,32,221,260,32],"7201747","mrkickling",[262,174,32,221,263,32],"7201813","mkmk",[265,266,42,240,267,32],"7202100",12,"lukaszg",[95,31,48,254,96,32],[270,271,37,214,272,32],"7201553",14,"CoryG89",[274,271,37,275,276,32],"7201690","project\u002Fneutral\u002Fdocs","tbirdz",[278,271,32,221,279,32],"7202078","th3iedkid",[281,271,37,282,272,32],"7202164","maker\u002Fneutral\u002Fexecution",[284,188,32,218,285,32],"7204625","dotneter",[287,288,42,240,289,32],"7201733",16,"kjannis",[291,288,32,232,10,42],"7201738",[293,288,48,294,289,32],"7201748","project\u002Fpositive\u002Fprivacy",[296,288,42,240,297,32],"7201786","nwienert",[60,299,48,191,61,32],17,[150,301,42,193,151,32],18,[303,301,32,195,10,42],"7202523",[305,306,42,240,307,32],"7201569",19,"runekaagaard",[119,306,32,232,10,42],[310,306,42,240,311,32],"7201854","The_Double",[313,314,42,193,315,32],"7202281",20,"plus9z",[317,33,42,240,318,32],"7201657","yojo",[122,33,32,232,10,42],[321,33,37,229,322,32],"7201796","selmnoo",[324,33,32,221,325,32],"7202075","jiggy2011",[327,33,42,328,329,32],"7201844","project\u002Fcritical\u002Fexecution","Aaronn",[135,17,42,193,136,32],[332,333,42,328,334,32],"7201640",23,"jhuckestein",[336,333,32,337,10,42],"7201646","maker\u002Fneutral\u002Fnone",[339,340,37,341,342,32],"7201877",24,"project\u002Fneutral\u002Fperformance","dpweb",[344,340,37,341,84,32],"7201907",[346,340,37,341,347,32],"7202012","dvanduzer",[349,350,32,221,351,32],"7201966",25,"instakill",[353,354,42,193,355,32],"7201881",26,"waxjar",[357,358,361,364,367,372,375],{"id":4,"t":11,"points":13,"comments":14},{"id":359,"t":360,"points":30,"comments":32},"7988792",1404483451,{"id":362,"t":363,"points":187,"comments":32},"8510743",1414320263,{"id":365,"t":366,"points":42,"comments":32},"9232657",1426779356,{"id":368,"t":369,"points":370,"comments":371},"9795872",1435539515,59,29,{"id":373,"t":374,"points":37,"comments":32},"10733702",1450125901,{"id":376,"t":377,"points":288,"comments":37},"34150158",1672158852,[379,384,389,394,399,404],{"id":380,"name":381,"points":382,"category":383},"7201353","InstantClick",426,"languages",{"id":385,"name":386,"points":387,"category":388},"7224436","Siri-as-a-Service Speech API",242,"ai",{"id":390,"name":391,"points":392,"category":393},"7191187","Eliss Infinity",214,"games",{"id":395,"name":396,"points":397,"category":398},"7188119","Hacker News Hack",149,"consumer_social",{"id":400,"name":401,"points":402,"category":403},"7200043","Automatic VPN Generator",125,"security_privacy",{"id":405,"name":406,"points":407,"category":408},"7219025","Abacus",120,"web_saas",false,"v2",{"id":412,"name":5,"line":5,"ai":409,"cat":19,"year":12,"points":13,"comments":14,"rec":27,"s":413,"top":17,"kw":414,"maker":10,"domain":9,"tier":18,"attempts":239,"strip":415,"url":8,"mix":416,"praise":79,"objection":100,"sub":20},7201405,-0.37,[23,24,25,26],"5115113100033111135015330153111113111331",[30,31,32,33],1793990902686]