positivenumbers are all store as
binary, so we don’t really need to worry about it.
bitmask 0xfto get the last 4 bits.
- Use a string ‘0123456789abcdef’ and a num’s
Mod with 16to get the char we want. (That’s smart!)
Given an integer
num, return a string representing its hexadecimal representation. For negative integers,
two’s complement method is used.
All the letters in the answer string should be lowercase characters, and there should not be any leading zeros in the answer except for the zero itself.
Note: You are not allowed to use any built-in library method to directly solve this problem.
Input: num = -1