Question

First, I don’t know if the title is appropriate for what I want to do. Maybe it has another name.

So let’s say I have a list ordered as follows:

dog1
dog2
dog3
cat1
cat2
cat3
hen1
hen2
hen3

and what I want is

dog1
cat1
hen1
dog2
cat2
hen2
dog3
cat3
hen3

Is there a standard algorithm for this, or is it user’s choice? What I was thinking was numbering them first and then bringing out the index in front.

11dog1
22dog2
33dog3
14cat1
25cat2
36cat3
17hen1
28hen2
39hen3

From there I would sort them and then remove the index. Is there a more elegant way?

Answer 1

My idea is that you separate each line in individual arrays.

array1 -> dog1, dog2, dog3
array2 -> hen1, hen2, hen3
array3 -> cat1, cat2, cat3

Then create another array where to store the result and do something like this:

string result[array1.length + array2.length + array3.length];
int counter = 0;
for(int i = 0; i < array1.length; i++) {
    result[counter] = array1[i];
    result[counter + 1] = array2[i];
    result[counter + 2] = array3[i];

    counter += 3;
}