Given two integers a and b, return how many times a can be halved while still being greater than b.
halveCount(1324, 98) ➞ 3
// (1324 -> 662 -> 331 -> 165.5)
halveCount(624, 8) ➞ 6
// (624 -> 312 -> 156 -> 78 -> 39 -> 19.5 -> 9.75)
halveCount(1000, 3) ➞ 8
// (1000 -> 500 -> 250 -> 125 -> 62.5 -> 31.25 -> 15.625 -> 7.8125 -> 3.90625)
Integer a will always be able to be halved at least once in every test case.