Javascript to obtain random numbers

<script type="text/javascript">
  function getRandom(n,m){
    var n=Number(n);  //Captive conversion to numbers    var m=Number(m);
    if(isNaN(n)||isNaN(m)){  //Distinguish whether it is a valid number. If one of the numbers is not a valid number, it returns a random decimal between [0, 1)      return ();
    }
    if(n>m){   //If n>m, then exchange      var temp=n;
      n=m;
      m=temp;
    }
    return (()*(m-n)+n);

  }
  //Get a random integer between five digits 0-50  var ary=[];
  for (var i=0;i<5;i++){
    (getRandom(0,50));
  }(ary);

</script>