Define a function that pairs 0 and 1 of the input array, 2 and 3, and so on, and then converts it to an integer and returns it

Examples:

SwapPlacesByGroup([1,2,3,4]) --> 2143n
SwapPlacesByGroup([0,5,2,3]) --> 5032n

Note: Returns undefiend if the length of the array is odd or the array is not a numeric array

Good luck!