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# Cant understand what kind of design to apply

In this challenge, we have the following geographical coordinates

Eiffel Tower - lat: 48.8582, lon: 2.2945 Great Pyramid - lat: 29.9792, lon: 31.1344 Sydney Opera House - lat: 33.8587, lon: 151.2140

Declare a function named coordinates that takes a single parameter of type String, with an external name for, a local name of location, and returns a tuple containing two Double values (Note: You do not have to name the return values). For example, if I use your function and pass in the string "Eiffel Tower" as an argument, I should get (48.8582, 2.2945) as the value. If a string is passed in that doesn’t match the set above, return (0,0)

functions.swift
```// Enter your code below
func coordinates(for location: String)-> (Double, Double) {

var above = (0,0)

switch monuments {
case "Eiffel Tower": above = 48.8582; 2.2945
case "Great Pyramid": above = 29.9792; 31.1344
case "Sydney Opera House": above = 33.8587; 151.2140
default: above  = (0,0)
}
return (above, monuments)

}
let findAll = coordinates(for: "Eiffel Tower")
```

That's fine: Here is a better answer.

So we are going to declare this function and then switch on its parameter.

```func coordinates(for location: String) -> (Double , Double ) {
switch location { // Switch on "location".
case "Eiffel Tower":
return (48.8582, 2.2945) // Return tuples
case "Great Pyramid":
return (29.9792, 31.1344 )
case "Sydney Opera House":
return (33.8587, 151.2140 )
default:
return (0.0 , 0.0) // Return Tuple of (0.0,0.0) if they input wrong city
}
}
```

Noticed that we didn't have to create extra variables ?

good luck.

Thanks, its working!) Now i see all mistakes and logic!)

Hello :

I'm going to guide you a bit through your answer, and see if you can figure out what is wrong with it yourself.

See the comments in your code below.

```// Enter your code below
func coordinates(for location: String)-> (Double, Double) {

var above = (0,0) // You are declaring a tuple with 0 values.

switch monuments { // monuments ? Where is this value coming from ?
case "Eiffel Tower": above = 48.8582; 2.2945 // <--- In Swift we should avoid using ( ; )
case "Great Pyramid": above = 29.9792; 31.1344
case "Sydney Opera House": above = 33.8587; 151.2140
default: above  = (0,0) // <--- are you re-assigning 0 values to an already declared 0 value tuple?
}
return (above, monuments)

}

let findAll = coordinates(for: "Eiffel Tower")
```

Your switch is "Switching" on an non existing value. Perhaps you should look into switching the parameter label from the function.

After you look at your code, and try to fix it, let me know how it goes. If you do not understand it still, then I will help you further by giving you an answer.

Good luck.