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In our cat food store program, our printed
question is running up against the space

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where the user types their answer.

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To fix this, we need to add a space
on to the end of the user question.

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We can do this by taking the question
string and concatenating or

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joining a string consisting of
a single space on to the end of it.

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To concatenate two strings,
you just type a plus sign between them.

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So this code here we'll join
the strings A and B together and

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this would join the string some words and
more words together.

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Let me save this and run it.

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And here's the result.

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You can see that the string some words
is smashed together with more words.

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If we want a space between
the joint strings,

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we'll need to add it ourselves by
a concatenating a third string in there.

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Let me save this and re-run it.

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There we go, and now there's a space.

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We can also concatenate
strings stored in variables.

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So let's declare a new variable named
myString and storeString in it.

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And now, let's concatenate that
together with another string.

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Let me save that.

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And let's try running it,
there's the string from our variable,

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and here's the string we
concatenated onto it.

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One important thing to note, though,
is that simply concatenating onto

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a string stored in a variable doesn't
change the value in the variable.

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So, if we were trying to print
the content of my string again,

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let's try that real quick.

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You can see that my string still just
contains the value we originally assigned

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to it, a string.

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There's no abc on the end.

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To update the value in the variable,

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we need to assign the concatenated
value back to it.

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We can do that with the += operator.

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This will concatenate a new string
onto the string currently contained

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in the myString variable.

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And then assign that new
concatenated value back to myString.

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So let's try printing that updated value,
save this and try running it.

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And now you can see that myString
contains the updated value, a string abc.

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I can even concatenate additional
strings onto the updated strings.

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So let's add def and

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assign that back to myString and
then print the resulting value.

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And let's try running this,
and you can see that, first,

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we updated myString so
that it contained a string abc, and

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then we concatenated an additional
string onto that, a string abc def.

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This is what the myString variable
contains at the end of the program.

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So by assigning concatenated
strings back to the same variable,

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you can keep building up longer and
longer strings.

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Let's use string concatenation
to fix our ask method.

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We'll simply take the value that we're
passing to the write method, and

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concatenate a space onto the end of it.

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That will cause there to be a space
between the question that gets asked and

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the answer the user types.

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So make sure to save that,
and let's try running it.

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How many cans are you ordering?

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Let's say 55, and
there's a space there now.

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Right now, we're simply printing
the value the user enters so

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we can debug it, but it would be helpful
for the user to know what they entered, so

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let's make this a little more user
friendly and convert this into a sentence.

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We'll do that using string
concatenation again.

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We'll say you entered, As a string,

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and then concatenate that together
with the value in the entry variable.

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And concatenate that with
cans to end the sentence.

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Save that let's try running it.

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And whoops it joins the value we entered
together with the rest of the sentence but

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theres no spaces surrounding
the value we entered.

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So let's fix that.

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We simply need to add spaces onto the end
of the string we're adding before

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the entry and onto the start of
the string we're adding after the entry.

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Let's save that.

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And try running it again.

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Okay, that looks much better.