sortedunion.js

// Bonfire: Sorted Union
// Author: @codebubb
// Challenge: http://www.freecodecamp.com/challenges/bonfire-sorted-union?solution=function%20unite()%20%7B%0A%20%20%2F%2FImportant%3A%20You%20should%20not%20slice%20on%20arguments%20because%20it%20prevents%20optimizations%20in%20JavaScript%20engines%20(V8%20for%20example).%20Instead%2C%20try%20constructing%20a%20new%20array%20by%20iterating%20through%20the%20arguments%20object%0A%20%20args%20%3D%20new%20Array(arguments.length)%3B%0A%20%20for(var%20i%3D0%3B%20i%3Carguments.length%3B%20i%2B%2B)%7B%0A%20%20%20%20args%5Bi%5D%20%3D%20arguments%5Bi%5D%3B%0A%20%20%7D%0A%20%20args%20%3D%20args.reduce(function(a%2Cb)%7B%0A%20%20%20%20return%20a.concat(b)%3B%0A%20%20%7D)%3B%0A%20%20return%20args.filter(function(a%2Ci)%7B%0A%20%20%20%20return%20args.indexOf(a)%20%3D%3D%20i%3B%0A%20%20%7D)%3B%0A%7D%0A%0A%0A%0A%0Aunite(%5B1%2C%203%2C%202%5D%2C%20%5B5%2C%202%2C%201%2C%204%5D%2C%20%5B2%2C%201%5D)%3B%0A
// Learn to Code at Free Code Camp (www.freecodecamp.com)

function unite() {
  //Important: You should not slice on arguments because it prevents optimizations in JavaScript engines (V8 for example). Instead, try constructing a new array by iterating through the arguments object
  args = new Array(arguments.length);
  for(var i=0; i<arguments.length; i++){
    args[i] = arguments[i];
  }
  args = args.reduce(function(a,b){
    return a.concat(b);
  });
  return args.filter(function(a,i){
    return args.indexOf(a) == i;
  });
}