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iOS

Posted by Lana Wong
Lana Wong
3,968 Points

I do not understand

When I tried this, the point instance is the same. Could you tell me why, and what is wrong with my code? Thank you.

let x1 = 0 let y1 = 0

let coordinate1: (x: Int, y: Int) = (0,0) coordinate1.x

struct Point{ let x: Int let y: Int

init(x: Int, y: Int){
    self.x = x
    self.y = y
}

func surroundingPoints(withRange range: Int = 1) -> [Point]{ var results: [Point] = [] for xCoord in (x-range)...(x+range) { for yCoord in (y-range)...(y+range) { let corrdinatePoint = Point(x: xCoord, y: yCoord) results.append(coordinatePoint) } } return results

} }

let coordinatePoint = Point(x: 0, y: 0) coordinatePoint.surroundingPoints()

Lana Wong
Lana Wong
3,968 Points

When posting, the code became all on one line, so it looks very weird.

1 Answer

Jeroen de Vrind
Jeroen de Vrind
29,772 Points
Jeroen de Vrind
Jeroen de Vrind
29,772 Points

Hi Lana, a few things you can get rid off first: you don't use x1, y1 and coordinate1 so u can remove this. Just like the initializer. Structs give u this initializer for free, so you don't need to write them yourself. With classes it's another case, then you should add the init method. You can remove the init method for this struct.

Because you added a default argument to the parameter in your surroundingPoints(with Range:) method, you get the same results based on this default argument every time when you call this` function without values for this argument, like you did in:

coordinatePoint.surroundingPoints()

If you call this method with a value for the argument, e.g.

coordinatePoint.surroundingPoints(withRange:3)

I'm sure you'll get a different result.