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iOS Swift Basics (retired) Operators Unary Operators

John Moron
John Moron
1,658 Points
Posted by John Moron
John Moron
1,658 Points

What is the value of totalScore? var totalScore = 10 - 20 ++totalScore

I don't understand this question.

3 Answers

Logan R
Logan R
22,989 Points
Logan R
Logan R
22,989 Points 
What is the value of totalScore? 
var totalScore = 10 - 20 
++totalScore

So what is happening is it is declaring a variable called totalScore. Total score is initialized with (10 - 20), so the initial value of totalScore is equal to -10.

With the ++ and -- operator, it is the same as saying:

totalScore = totalScore + 1

It is just a really shortened way of saying it.

The answer to the question is -9.

var totalScore = 10 - 20 // This equals -10
++totalScore             // This takes -10 and adds one to make -9
agreatdaytocode
agreatdaytocode
24,757 Points
agreatdaytocode
agreatdaytocode
24,757 Points

Hi John

If you put this into a playground file you will get the answer 

var totalScore = 10 - 20  \\ - 10
++totalScore \\ -9
John Moron
John Moron
1,658 Points
John Moron
John Moron
1,658 Points

ohh I got it now thanks.

Logan R
Logan R
22,989 Points
Logan R
Logan R
22,989 Points

No problem! If you need any further clarification, just simply ask :)