Obfuscated JavaScript
Given enough time, any language will evolve into Perl.
($=(_,__=0)=>_?$(_.slice(1),+_[0]?__+(2**(_.length-1)):__):__)("10"); // --> 2 function binstr2dec(binstr, num=0) { if(binstr.length) { if(parseInt(binstr.substring(0, 1), 10)) { num += Math.pow(2, binstr.length - 1); } const rest = binstr.substring(1); return binstr2dec(rest, num); } else { return num; } }
(_=$=>$<=0?1:$*_($-1))(5); // --> 120 function factorial(n) { if(n <= 0) { return 1; } return n * factorial(n - 1); }
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