Fixed optional unwrapping

ProjectClock/AlarmActivationViewController.swift

@@ -38,7 +38,7 @@ class AlarmActivationViewController: UIViewController
         
         timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: #selector(AlarmActivationViewController.playSound), userInfo: nil, repeats: true)
         setAlarmType()
-        print(MathExpression.random())
+        //print(MathExpression.random())
     }
     
     @objc func playSound()
@@ -68,8 +68,13 @@ class AlarmActivationViewController: UIViewController
     }
     
     @IBAction func checkPuzzleSolution(_ sender: Any) {
-        if puzzleAnswers.contains(Int(puzzleAnswerInput.text!)!) {
-            print("alarm solved")
+        if let input = puzzleAnswerInput.text {
+            if let numericalInput = Int(input) {
+                if puzzleAnswers.contains(numericalInput) {
+                    timer?.invalidate()
+                    print("Alarm solved")
+                }
+            }
         }
     }
 }

ProjectClock/Base.lproj/Main.storyboard

@@ -1,9 +1,9 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="17701" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="s8U-C8-W2S">
+<document type="com.apple.InterfaceBuilder3.CocoaTouch.Storyboard.XIB" version="3.0" toolsVersion="17156" targetRuntime="iOS.CocoaTouch" propertyAccessControl="none" useAutolayout="YES" useTraitCollections="YES" useSafeAreas="YES" colorMatched="YES" initialViewController="s8U-C8-W2S">
     <device id="retina6_1" orientation="portrait" appearance="light"/>
     <dependencies>
         <deployment identifier="iOS"/>
-        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="17703"/>
+        <plugIn identifier="com.apple.InterfaceBuilder.IBCocoaTouchPlugin" version="17125"/>
         <capability name="Safe area layout guides" minToolsVersion="9.0"/>
         <capability name="System colors in document resources" minToolsVersion="11.0"/>
         <capability name="documents saved in the Xcode 8 format" minToolsVersion="8.0"/>

ProjectClock/MathExpressions.swift

@@ -139,7 +139,7 @@ class QuadraticProb {
         let b = root1 + root2 //bx
         let c = root1 * root2 //x
         
-        return "x^2 + \(b) + \(c)"
+        return "x^2 + \(b)x + \(c)"
     }
     
     /**