1 files changed, 41 insertions, 0 deletions
diff --git a/src/calculator.swift b/src/calculator.swift
new file mode 100644
index 0000000..dfd4c4c
--- /dev/null
+++ b/src/calculator.swift
@@ -0,0 +1,41 @@
+enum InvalidOperatorError: Error {
+    case operatorNotSupported
+}
+
+func calculate(operatorThing: String, number1: Float, number2: Float) throws -> Float {
+    switch operatorThing {
+    case "+":
+        return number1 + number2
+    case "-":
+        return number1 - number2
+    case "/":
+        return number1 / number2
+    case "*":
+        return number1 * number2
+    default:
+       throw InvalidOperatorError.operatorNotSupported
+    }
+}
+
+
+func main() {
+    print("enter a number:")
+    let number1 = Float(readLine()!)!
+    print("enter an operator:")
+    let operatorThing = readLine()!
+    print("enter another number:")
+    let number2 = Float(readLine()!)!
+    
+    do {
+        let result = try calculate(operatorThing: operatorThing, number1: number1, number2: number2) 
+        print(result)
+    } catch InvalidOperatorError.operatorNotSupported {
+        print("invalid operator!")
+        return
+    } catch {
+        print("unexpected error!")
+        return
+    }
+}
+
+main()