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iOS Swift Basics Swift Operators Working With Operators: Part 2

Posted by Tony Winchester
Tony Winchester
11,462 Points

Stuck on Swift 3: Working with operators Challenge Part 2

This is the Question:

In this game of ours, we have an odd scoring mechanism . At the end of the round, if your score is 10, you lose! If it's anything but 10, you win.

Declare a constant named isWinner and assign the results of a comparison operation to check whether the player has won or not. For example, if the total score is not 10, then the player has won and isWinner should equal true. (Hint: Use the NOT operator)

What is wrong with my code below? I get an error telling me I should make sure to use the NOT operator.. But obviously I did! Why is the system not accepting my code?

operators.swift 
// Enter your code below

var initialScore = 8
let totalScore = initialScore += 1

let isWinner = (totalScore != 10)

3 Answers

Toby Morgan
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Toby Morgan
iOS Development Techdegree Graduate 23,133 Points
Toby Morgan
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Toby Morgan
iOS Development Techdegree Graduate 23,133 Points

Change the line:

let totalScore = initialScore += 1

With:

let totalScore = initialScore + 1

(i.e. remove the extra equals assignment operator)

Tomas Salas
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Tomas Salas
Front End Web Development Techdegree Graduate 37,934 Points
Tomas Salas
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Tomas Salas
Front End Web Development Techdegree Graduate 37,934 Points

let totalScore = initialScore += 1

you are trying to use Compound Assignment Operator in a circumstance that is not build for it.

try using a unary operator instead ...initalScore + 1

Tony Winchester
Tony Winchester
11,462 Points
Tony Winchester
Tony Winchester
11,462 Points

Thank you for the suggestions, but if I do that it still doesn't work, I get the response "Make sure you use the unary plus operator to increase the initial score by 1"

Toby Morgan
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Toby Morgan
iOS Development Techdegree Graduate 23,133 Points
Toby Morgan
.a{fill-rule:evenodd;}techdegree seal-36
Toby Morgan
iOS Development Techdegree Graduate 23,133 Points

So if it wants you to incremet using the unary operator do

let totalScore = initialScore++

or 

let totalScore = ++initialScore

Depending on whether you want to increment it before or after the assignment.

BTW - the unary operators ++ and -- are deprecated in Swift 3.