lcm.js

/*
let rec gcd a b =
     match a, b with
     | _ , 0 -> a
     | _ , _ -> gcd b (a%b)

let lcm a b = a * b / (gcd a b)
*/

var arr = [1,2,3,4,5]
var lcmList = function(a) {
    var gcd = function(a,b){
        if(b==0){
            return a;
        }else{
            return gcd(b,a%b)
        }
    }
    var lcm = function(a,b){
        return a*b/gcd(a,b)
    }
    return a.reduce(lcm)
}
lcmList(arr)