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Python Python Basics Types and Branching Strings and Operators

Can someone please help me, im trying to understand what += does in this code

can someone please help me with this question im trying to understand what the += is used for.

https://teamtreehouse.com/library/strings-and-operators

snacks = "cake" + " and custard"
snacks = snacks + " and tea"
snacks += ", lovley"
snacks
'cake and custard and tea, lovley'

5 Answers

Jennifer Nordell
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STAFF
.a{fill-rule:evenodd;}techdegree
Jennifer Nordell
Treehouse Teacher

Hi there, Jamshaid Ali! The += is really just a shorthand. It means, take the value that was in this variable, add something to it and reassign it back into that variable. The result is cumulative.

greeting = "Hi"
greeting += " there, Jamshaid"
greeting += "!"

print(greeting)

This will print out "Hi there, Jamshaid!". Each time we use the += we're taking the original value and adding on a new string to the end. But you could also write this out the long way:

greeting = "Hi"
greeting = greeting + " there, Jamshaid"
greeting = greeting + "!"

print(greeting)

This would give you the same results. Take the original value. Add something to it and assign the result back into the variable overwriting the original value with the cumulative value.

Hope this helps! :sparkles:

let's say
a = 2

a=a+3 -------The value of a will be equals to 5.

instead of writing a=a+3, we can also write a+=3. The result will be the same.

ok thank you

Thank you for breaking it down. I understand it now too

another way to see it... think of the " + " in the equation there would be considered you adding another string to the pre-existing string. Then the " = " would be considered you applying both together. So essentially, "dessert += "!" * 20" really just means "add (whatever dessert was for you) the dessert string to this new one, "!", and apply them together. equaling (my dessert)... Strawberries and Bananas and Ice Cream, yum!!!!!!!!!!!!!!!!!!!! .