I have an array with dates in ascending order, I am trying to create a Snowflake UDF to count the array element between two dates.

The function should get the two days and tell us the count between the two days.

    create or replace function workdays_between(date1 String, date2 String)
 RETURNS double
  LANGUAGE JAVASCRIPT
  as 
  $$
  var DATE1 = DATE1
  var DATE2 = DATE2
  var count = 1
  var i = 1
  a = ["2017-01-01","2017-01-02","2017-01-03","2017-01-06","2017-01-09","2017-01-10"]
  if (DATE1 < DATE2) {
    for (i=1;a[i]<=DATE2;i++) {
        if (a[i] >= DATE1) {
         count = count + 1;
         }
      }
  }
    else
    {
        for (i=1;a[i]<=DATE1;i++) {
        if (a[i] >= DATE2) {
         count = count + 1;
        }
        }
        count = count * -1;
  }
     return count;
  $$

But I am not getting the desired output, please help.