getNumberSpace function
This method returns the space between two numbers as an integer.
Implementation
int getNumberSpace(String numberOne, String numberTwo) {
int numberOneInt = int.tryParse(numberOne) as int;
assert(numberOneInt is int);
int numberTwoInt = int.tryParse(numberTwo) as int;
assert(numberTwoInt is int);
int space = numberTwoInt - numberOneInt;
return space;
}