Without using arrays or strings, write a method that returns the number of occurrences of a particular set of digits within a positive integer. For example, the set of digits 73 occurs 2 times in the number 731773. Two parameters will be passed in. As preconditions, you may assume that 'num' will be positive and 'target' will be a positive integer with fewer digits than 'num'. Return the number of time 'target' occurs in 'num'. Note that LEADING zeros are NOT allowed.