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Not operator

Declare a constant named isWinner and assign the results of a comparison operation to check whether the player has won or not. If the total score is not 10, then the player has won, otherwise he or she has lost. (Hint: Use the NOT operator)

Hey there! Please post what you have tried or try to explain what you are struggling with. The community here is keen to help, but the idea is to ask questions. Posting the solutions to an assignment should be the very last step of an explanation :)

You can use the not operator, `!` with `NSNumber#isEqualToNumber`. Alternatively, you could technically use the does not equal operator. Just be sure you compare primitives to primitives or use a method that will compare objects such as `NSNumber#isEqualToNumber`.

If you use `isEqualToNumber`, you will have to wrap any primitive numbers with `NSNumber`

See example code below with comments

```var scoreLimit = 10

var a = 5
var b = 2

var c = NSNumber(int: 10)

if !c.isEqualToNumber(NSNumber(integer: scoreLimit)) {
print("C does not equal \(scoreLimit)")
}

if a != scoreLimit {
print("A does not equal \(scoreLimit)")
}

if b != scoreLimit {
print("B does not equal \(scoreLimit)")
}
```

Just a small addition: if you wanted to use the ! operator as a prefix, you could also write

```if !(a == scoreLimit) {
print("A does not equal \(scoreLimit)")
}
```

@samarth sharma: The key to this challenge is indeed the `!=` (not equal) operator, though :)

Martin Wildfeuer Many ways to solve the problem :)

The hint leads towards `!(a == scoreLimit)` or `!a.isEqualToNumber(NSNumber(integer: scoreLimit))`

IRL, it doesn't matter as long as it's readable and correct.

hey guys thanks for your prompt reply.. i was stuck initially with the following code:

let isWinner = totalScore

totalScore == 10

i was getting an error. i re-read the question multiple times and tried to figure out the logic.

finally, i wrote the following code and was correct

let isWinner = totalScore != 10

thanks for the answers again as they showed me the alternative ways to execute the same command :)