Write syntactically correct Javascript code to sort an array of sub-arrays containing integers using the sort and reduce array functions as described below. You will sort the sub-arrays in ascending order by the maxium value found in each sub-array. Your solution would be executed in the following manner:

var x = [ [ 2 , 5 , 1 ], [ 1 , 23 ] , [ 3 ] , [ 22, 16, 8 ] ] ;

x.sort(compare);

will result in variable x containing [ 3 ] , [ 2, 5, 1], [ 22 , 16 , 8], [ 1 , 23 ] ]. The maximum value of each sub-array is shown here in bold. Your solution must be written so that when run with the code above, x will contain the sorted array.