Check if a numeric string is divisible by 8

## Problem You are given a **very large** non-negative integer represented as a string `s` (it may be too large to fit in standard integer types). Write a function that returns `True` if the number represented by `s` is divisible by **8**, otherwise return `False`. ### Constraints / Requirements - Do **not** convert the entire string to an integer type (e.g., no `int(s)`). - `s` consists only of digits `'0'`–`'9'`. - Leading zeros may exist (e.g., `"00016"`). ## Examples - `s = "16"` → `True` - `s = "123"` → `False` - `s = "1000"` → `True`