Count number of values in array between two input values

Question

As the title suggests, I want to create a function the counts the number of values in my array between two values that have been entered by the user. So for example, if the arra

Answer 1

You can use Array.prototype.filter(), RegExp.prototype.test() with RegExp constructor with class from-to, where from is 5, to is 7, get .length of resulting array

var from = 5;
var to = 7;
var len = arr.filter(RegExp.prototype.test.bind(new RegExp(`[${from}-${to}]`))).length;

You can alternatively use .toString(), .match()

var arr = [1,4,6,7,8,6];
var from = 5;
var to = 7;
var res = arr.toString().match(new RegExp(`[${from}-${to}]`, "g"));
var len = res.length;

console.log(res.length);