/*
Description:
Return product of numbers between a and b (both non-negative). If it’s impossible then return ‘Error’ in JavaScript or throw an exception in C#.
For example:
product(2,5) => 3 * 4 = 12
product(5,2) => ‘Error’ / Exception
*/
function product(a,b){
let arr = [];
for (let i=a+1;ia*b,1)
}