diff --git a/archive/s/swift/prime-number.swift b/archive/s/swift/prime-number.swift new file mode 100644 index 000000000..999d98137 --- /dev/null +++ b/archive/s/swift/prime-number.swift @@ -0,0 +1,32 @@ +import Foundation + +let usage = "Usage: please input a non-negative integer" + +if CommandLine.arguments.count != 2 { + print(usage) + exit(0) +} + +guard let number = Int(CommandLine.arguments[1]), number >= 0 else { + print(usage) + exit(0) +} + +if number < 2 { + print("composite") + exit(0) +} + +var isPrime = true +let limit = Int(Double(number).squareRoot()) + +if limit >= 2 { + for i in 2...limit { + if number % i == 0 { + isPrime = false + break + } + } +} + +print(isPrime ? "prime" : "composite") \ No newline at end of file