Java Taskbook Level 3.9

Given a certain line, for example, like this:

String str = "023m0df0dfg0";

Print to the console the positions of all zeros in this line.

Given some array, for example, like this:

int arr = {1, 2, 3, 4, 5, 6};

Divide the sum of the first half of the elements of this array by the sum of the second half of the elements.

Given an array of strings:

String[] arr = {"ab", "cd", "ef"};

Get an array of characters from these strings:

chars[] {'a', 'b', 'c', 'd', 'e', 'f'};

Two arrays are given:

int[] arr1 = {1, 2, 3};
int[] arr2 = {4, 5, 6};

Loop through these arrays and print their elements in each iteration as follows:

"1,4"
"2,5"
"3,6"

Given some integer:

int num = 12;

Convert it to binary.