- Added Swift solution to the task "Esthetic Number" of week 173.

1 files changed, 63 insertions, 0 deletions

diff --git a/challenge-173/mohammad-anwar/swift/ch-1.swift b/challenge-173/mohammad-anwar/swift/ch-1.swift
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+++ b/challenge-173/mohammad-anwar/swift/ch-1.swift
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+import Foundation
+
+/*
+
+Week 173:
+
+    https://theweeklychallenge.org/blog/perl-weekly-challenge-173
+
+Task #1: Esthetic Number
+
+    You are given a positive integer, $n.
+
+    Write a script to find out if the given number is Esthetic Number.
+
+*/
+
+enum ParamError: Error {
+    case missingNumber
+    case invalidNumber
+}
+
+do {
+    let paramCount:Int = Int(CommandLine.argc)
+
+    if paramCount <= 1 {
+        throw ParamError.missingNumber
+    }
+
+    let num:Int = Int(CommandLine.arguments[1])!
+    if num > 0 {
+        print(isEstheticNumber(num))
+    }
+    else {
+        throw ParamError.invalidNumber
+    }
+}
+catch ParamError.missingNumber {
+    print("Missing number.")
+}
+catch ParamError.invalidNumber {
+    print("Invalid number.")
+}
+catch let error {
+    print(error)
+}
+
+//
+//
+// Function
+
+func isEstheticNumber(_ n:Int) -> Bool {
+    let s:String = String(n)
+    let l:Int    = s.count - 1
+    for i in 1...l {
+        let a:Int = Int(String(Array(s)[i - 1]))!
+        let b:Int = Int(String(Array(s)[i]))!
+        if abs(a - b) != 1 {
+            return false
+        }
+    }
+
+    return true;
+}