find the area of a regular polygon in swift

main.swift
func areaOfRegularPolygon(n: Int, s: Double) -> Double {
    let numerator = Double(n) * pow(s, 2)
    let denominator = 4 * tan(Double.pi / Double(n))
    return numerator / denominator
}
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main.swift
area = (n * s^2) / (4 * tan(pi / n))
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main.swift
let n = 5  // pentagon
let s = 10.0  // side length is 10 units
let area = areaOfRegularPolygon(n: n, s: s)
print("The area of the regular polygon is \(area) square units.")
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main.swift
The area of the regular polygon is 237.76429123254518 square units.
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