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In this exercise,

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the goal is to write a program that adds the digits

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in a two-digit number.

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So for example, right now you should see that

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in the input pane there is a number and it is 39.

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Now, after it gets processed by your code inside main.py,

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your code should print out the value 3+9,

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which is equal to 12.

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Figure out how you can do this using what you've learned

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about data types, inputs and the print function.

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And once you think your code is doing

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what it's supposed to,

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click on the submit button to check your code.

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Now we have to do this in a few steps.

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So I'm going to walk you step by step through each of them.

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Now, how can we get hold of the first digit

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and the second digit separately from the input?

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Well, one thing you could have tried is you

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could have used type checking to check what is

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the data type that I'm getting through this input function?

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What is it that I can get hold of?

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And if you tried that, you see

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that the input comes in in the data type of a string.

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What we know about strings is

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that we saw that we can use a square bracket

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after a string and put in the position

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of the character in the string that we want to access.

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If we get the two-digit number variable, add square brackets [ ]

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afterwards, and put in 0 as the index,

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so get the first character out of that string<

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then we'd end up with the first number, but as a string.

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So the next part is converting that string

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into a different data type, a number data type.

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And in this case, because it's a whole number that we want,

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we can simply use the int() function and then wrap

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that-two digit number, accessing the first digit,

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into that function, like this.

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So now we have the first digit as a number

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and we can do the same thing to get hold

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of the second digit, but this time accessing

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that variable two-digit number at position 1,

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which will get us the second number.

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And you can print these out just to verify

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and you can check the data type of the variable first digit

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and second digit, just to make sure that we are now

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getting hold of a number, which can be multiplied,

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subtracted, added, whatever it is you want to do with it.

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Finally, we can add the two digits together

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adding first digit to the second digit

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and then printing it out.

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Now of course you can write this program

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in a lot fewer lines.

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You can write it all in one line if you wanted to.

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But what I want you to remember is always think

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about readability.

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If somebody else came and read your code,

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would it be easily understood by that person

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or would they have to think

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and spend a lot of time in order to figure it out?

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Don't optimize for the least number of lines.

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It's called Code Golf, and it's not something to aspire to.

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Instead, aspire to make the most readable code

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and you'll have the happiest colleagues who work with you.