Write a method that accepts an array on integers called 'nums', then returns a new array made up of the differences between consecutive elements in 'nums'. For example, if 'nums' equals {5,10,13,11} you would return (5,3,-2} because the difference between 5 and 10 is 5, the difference between 10 and 13 is 3, etc. Note that the array being returned has one less element than 'nums'. As a precondition, you may assume that 'nums' has at least two elements.