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Start your free trialAl Hughes
iOS Development Techdegree Student 469 PointsCan't make sense of this
Can someone explain to my why the below question would not result on Zero instead of -100
What is the value of totalScore?
var levelScore = 100 var totalScore = -levelScore
1 Answer
Shade Wilson
9,002 PointsYou are confusing the -= operator and the negative (-) operator here. The value of totalScore would have been 0 if the code were written as follows:
var levelScore = 100
var totalScore = 100
totalScore -= levelScore
This is because using -= here is the same as saying:
totalScore = totalScore - levelScore.
However, the question is stated differently:
var levelScore = 100
var totalScore = -levelScore
Here the declaration of the variable totalScore is equivalent to the following:
var totalScore = -1 * levelScore
Thus, totalScore is simply -100.
Al Hughes
iOS Development Techdegree Student 469 PointsAl Hughes
iOS Development Techdegree Student 469 PointsThis clears it up perfectly. Thanks! I just wanted to make sure I fully understood before moving on.