function dist(){
  var s = ["a","ba","a","c"];   
  var arr = [], map = {};
  for(var i=0; i<s.length; i++){   
    var n = s[i];   
    if(!map.hasOwnProperty(n)){   
        map[n] = true;   
        arr.push(n);   
    }   
  }   
 alert(arr);
}


function dist1(){
var array=[2.3,2.3,"a","b","b",true,true,true,false,1,0,undefined,null];   
for(var i=0;i<array.length;i++){   
    for(var j=i+1;j<array.length;j++){   
       if(array[j]===array[i]) {   
           array.splice(j,1);   
           j--;   
         }   
          
    }   
}   
alert(array);
}