function removeDuplicates(num) {  
  var x,  
      len=num.length,  
      out=[],  
      obj={};  
   
  for (x=0; x<len; x++) {  
    obj[num[x]]=0;  
  }  
  for (x in obj) {  
    out.push(x);  
  }  
  return out;  
}  
var Mynum = [1, 2, 2, 4, 5, 4, 7, 8, 7, 3, 6];  
result = removeDuplicates(Mynum);  
console.log(Mynum);  
console.log(result);  