Three Simple Math Problems Added

Two simple Algebra Problem (one with two expressions and one with three expressions) and a quadratic problem

ProjectClock/MathExpressions.swift

@@ -33,9 +33,10 @@ enum MathOperator : String {
     case minus = "-"
     case multiply = "*"
     case divide = "/"
+    case power = "**"
 
     static func random() -> MathOperator {
-        let allMathOperators: [MathOperator] = [.plus, .minus, .multiply, .divide]
+        let allMathOperators: [MathOperator] = [.plus, .minus, .multiply, .divide, .power]
         let index = Int(arc4random_uniform(UInt32(allMathOperators.count)))
 
         return allMathOperators[index]
@@ -71,10 +72,10 @@ class MathExpression : CustomStringConvertible {
         return "\(leftString) \(self.operator.rawValue) \(rightString)"
     }
 
-    var result : Any? {
+    var result : Int? {
         let format = "\(lhs.nsExpressionFormatString) \(`operator`.rawValue) \(rhs.nsExpressionFormatString)"
         let expr = NSExpression(format: format)
-        return expr.expressionValue(with: nil, context: nil)
+        return expr.expressionValue(with: nil, context: nil) as? Int
     }
 
     static func random() -> MathExpression {
@@ -84,3 +85,71 @@ class MathExpression : CustomStringConvertible {
         return MathExpression(lhs: lhs, rhs: rhs, operator: .random())
     }
 }
+
+//WARNING: This code is ugly, and probably out of place...but it works!
+// Simple Problem - 2 expressions
+class AlgProb2  : MathExpression{
+let a = MathExpression.random()
+let b = MathExpression.random()
+
+
+    func getProblem() -> String {
+        let problem = ("\(a) + \(b)")
+        return problem
+    }
+    func getAnswer() -> String {
+        let answer = "\(a.result! + b.result!)"
+        return answer
+    }
+}
+// Simple Problem - 3 expressions
+class AlgProb3  : MathExpression{
+let a = MathExpression.random()
+let b = MathExpression.random()
+let c = MathExpression.random()
+
+    func getProblem() -> String {
+        let problem = ("\(a) + \(b) + \(c)")
+        return problem
+    }
+    func getAnswer() -> String {
+        let answer = "\(a.result! + b.result! + c.result!)"
+        return answer
+    }
+}
+
+
+class quadraticProb{
+    
+    let a = Int.random(in: 1...10)//ax^2
+    let b = Int.random(in: 1...10)//bx
+    let c = Int.random(in: 1...10)//c
+    var roots = [Int]()
+
+    
+    func getProblem() -> String{
+         return "\(a)x^2 + \(b)x + \(c)"
+    }
+
+    //finds the roots of the quadratic **NOTE**: the return type is [Int], not a String
+    func  getAnswer() -> [Int]{
+        let d = Int(pow(Double(b), 2) - 4 * Double(a) * Double(c)) // discriminant
+       
+        // if d>0 , equation has two distinct real roots exist.
+        if d > 0 {
+            let x1 = Int((-Double(b) + sqrt(Double(d)))/(2*Double(a)))
+            let x2 = Int((-Double(b) - sqrt(Double(d)))/(2*Double(a)))
+            roots = [x1, x2]
+        }
+        //if d=0, equation has two repeated real roots.
+        else if d == 0 {
+            let x = Int(-Double(b)/(2*Double(a)))
+            roots = [x]
+        }
+        //    if d<0 equation has two complex roots, but idk how to calculate that by hand, so we'll return nothing
+        else if d < 0 {
+            roots = []
+        }
+        return roots
+    }
+}