PHP Taskbook Level 3.9
Given a string, check that this string consists only of numbers.
Given a string, check that this string consists of only even digits.
Given an array of numbers, remove from it numbers that have two or more zeros.
Find all numbers from 1 to 1000 whose sum of digits is 13.
Create the following array using loops:
[
[1, 2, 3],
[4, 5, 6],
[7, 8, 9],
]
