# Programming Fundamentals/Arrays/Swift

## arrays.swift

```// This program uses arrays to display temperature conversion tables
// and temperature as an array subscript to find a given conversion.
//
// References:
//     https://www.mathsisfun.com/temperature-conversion.html
//     https://developer.apple.com/library/content/documentation/Swift/Conceptual/Swift_Programming_Language/TheBasics.html

import Foundation

func buildC(size: Int) -> [Double]
{
var c = [Double]()
var value: Double

for index in 0...size
{
value = Double(index * 9) / 5 + 32
c.append(value)
}

return c
}

func buildF(size: Int) -> [Double]
{
var f = [Double]()
var value: Double

for index in 0...size
{
value = Double((index - 32) * 5) / 9
f.append(value)
}

return f
}

func displayArray(name: String, array: inout [Double])
{
for index in 0...array.count - 1
{
print(name + "[" + String(index) + "] = " + String(array[index]))
}
}

func findTemperature(c: inout [Double], f: inout [Double])
{
var temp: Int
var size: Int

size = minimum(value1:c.count, value2:f.count)
repeat
{
print("Enter a temperature between 0 and " + String((size - 1)))
} while temp < 0 || temp > size - 1
print(String(temp) + "° Celsius is " + String(c[temp]) + "° Fahrenheit")
print(String(temp) + "° Fahrenheit is " + String(f[temp]) + "° Celsius")
}

func minimum(value1: Int, value2: Int) -> Int
{
var result: Int

if value1 < value2
{
result = value1
}
else
{
result = value2
}

return result
}

func main()
{
var c = buildC(size:100)
var f = buildF(size:212)
displayArray(name:"C", array:&c)
displayArray(name:"F", array:&f)
findTemperature(c:&c, f:&f)
}

main()
```

## Try It

Copy and paste the code above into one of the following free online development environments or use your own Swift compiler / interpreter / IDE.