Given two ints a and b, add all the numbers between a and b, inclusive. So if a is 4 and b is 7, the result should be 22, the result of 4+5+6+7. For all inputs, a < b is NOT a precondition (either a or b could be larger). However, a != b IS a precondition.

HINT

You should probably determine which of a and b is larger first.