Initial commit

src/main/java/com/example/LoopTestApplication.java

@@ -0,0 +1,13 @@
+package com.example;
+
+import com.example.util.AddFunction;
+import com.example.util.CalcFunction;
+
+public class LoopTestApplication {
+
+    public static void main(String[] args) {
+        System.out.println("============== Calculator =============");
+        CalcFunction add = new AddFunction();
+        System.out.println("ADDITION: " + add.calc(2, 5, 6));
+    }
+}

src/main/java/com/example/util/AddFunction.java

@@ -0,0 +1,12 @@
+package com.example.util;
+
+public class AddFunction implements CalcFunction {
+
+    public double calc(double... input) {
+        double sum = 0;
+        for (double i : input) {
+            sum += i;
+        }
+        return sum;
+    }
+}

src/main/java/com/example/util/CalcFunction.java

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+package com.example.util;
+
+public interface CalcFunction {
+
+    double calc(double... input);
+}