How can I extract the places values of a number?

Question

I'm working on a math game in the Unity game engine using C#, specifically a reusable component to teach the grid method for multiplication. For example, when given the numbers 34 and 13, it should generate a 3X3 grid (a header column and row for the multiplier and multiplicand place values and 2X2 for the number of places in the multiplier and multiplicand). Something that looks like this:

My issue is that I don't know the best way to extract the place values of the numbers (eg 34 -> 30 and 4). I was thinking of just converting it to a string, adding 0s to the higher place values based on its index, and converting it back to an int, but this seems like a bad solution. Is there a better way of doing this?

Note: I'll pretty much only be dealing with positive whole numbers, but the number of place values might vary.

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Thanks to all who answered! Thought it might be helpful to post my Unity-specific solution that I constructed with all the replies:

List<int> GetPlaceValues(int num) {
    List<int> placeValues = new List<int>();
    while (num > 0) {
        placeValues.Add(num % 10);
        num /= 10;
    }
    for(int i = 0;i<placeValues.Count;i++) {
        placeValues[i] *= (int)Mathf.Pow(10, i);
    }
    placeValues.Reverse();
    return placeValues;
}

Answer 1

Take advantage of the way our number system works. Here's a basic example:

string test = "12034";
for (int i = 0; i < test.Length; ++i) {
    int digit = test[test.Length - i - 1] - '0';
    digit *= (int)Math.Pow(10, i);
    Console.WriteLine("digit = " + digit);
}

Basically, it reads from the rightmost digit (assuming the input is an integer), and uses the convenient place value of the way our system works to calculate the meaning of the digit.

test.Length - i - 1 treats the rightmost as 0, and indexes positive to the left of there.

- '0' converts from the encoding value for '0' to an actual digit.

Play with the code