Data update

Task/Canonicalize-CIDR/Swift/canonicalize-cidr.swift

@@ -0,0 +1,41 @@
+import Foundation
+
+func dottedToInt(_ dotted: String) -> UInt32 {
+    let digits = dotted.split(separator: ".").map { UInt32($0)! }
+    return digits.enumerated().reduce(0) { $0 + ($1.element << (24 - $1.offset * 8)) }
+}
+
+func intToDotted(_ ip: UInt32) -> String {
+    let digits = [24, 16, 8, 0].map { (ip & (255 << $0)) >> $0 }
+    return digits.map { String($0) }.joined(separator: ".")
+}
+
+func networkMask(_ numberOfBits: Int) -> UInt32 {
+    // Explicitly use UInt32 for bitwise operations
+    return UInt32((1 << numberOfBits) - 1) << (32 - numberOfBits)
+}
+
+func canonicalize(_ ip: String) -> String {
+    let parts = ip.split(separator: "/")
+    let dotted = String(parts[0])
+    let networkBits = Int(parts[1])!
+
+    let i = dottedToInt(dotted)
+    let mask = networkMask(networkBits)
+    return "\(intToDotted(i & mask))/\(networkBits)"
+}
+
+let testCases = [
+    ("36.18.154.103/12", "36.16.0.0/12"),
+    ("62.62.197.11/29", "62.62.197.8/29"),
+    ("67.137.119.181/4", "64.0.0.0/4"),
+    ("161.214.74.21/24", "161.214.74.0/24"),
+    ("184.232.176.184/18", "184.232.128.0/18"),
+]
+
+for testCase in testCases {
+    let (ip, expect) = testCase
+    let result = canonicalize(ip)
+    print("\(ip) -> \(result)")
+    assert(result == expect, "Test failed for \(ip)")
+}