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@janjongboom
Created April 27, 2012 12:18
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isEven function for javascript
// efficient isEven function
// you can insert a number or a string, doesn't matter
// it doesn't take numbers after the dot into account because noone uses them anyways
// it's also very handy for shopping websites because you can do
// isEven("$ 31.00") and it will say 'not even'.
// or isEven("32.00 $") and will say 'even'
function isEven(a) {
   a = a.toString().replace(/[^0-9.]/g, "");
   var stack = [];
   var rev = a.split('').reverse();
   for (var ix = 0; ix < rev.length; ix++) {
       if (rev[ix] == ".") stack.push("dot")
       else if (rev[ix] == "1" || rev[ix] == "3" || rev[ix] =="5" || rev[ix] == "7" || rev[ix] == "9")
          stack.push("odd")
       else
          stack.push('even')
   }
   var wholenumber = stack.splice(stack.indexOf("dot") + 1)
   return wholenumber[0] == "even";
}
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