Merge pull request #3 from EmilianoAngel/solutions

#27 - Dart

Author: EmilianoAngel

Roadmap/27 - SOLID OCP/dart/EmilianoAngel.dart

@@ -0,0 +1,119 @@
+// Incorrecto
+// class Form {
+
+//   void drawSquare() {
+//     print('Dibujar un cuadrado');
+//   }
+
+//   void drawCircle() {
+//     print('Dibujar un círculo');
+//   }
+// }
+
+// Correcto
+abstract class Form {
+  void draw() {}
+}
+
+class Square extends Form {
+  @override
+  void draw() {
+    print('Dibujar un cuadrado');
+  }
+}
+
+class Circle extends Form {
+  @override
+  void draw() {
+    print('Dibujar un círculo');
+  }
+}
+
+class Triangle extends Form {
+  @override
+  void draw() {
+    print('Dibujar un triángulo');
+  }
+}
+
+// Ejercicio de calculadora
+
+abstract class Operation {
+  double execute(double a, double b) {
+    return 0;
+  }
+}
+
+class Addition extends Operation {
+  @override
+  double execute(double a, double b) {
+    return a + b;
+  }
+}
+
+class Subtraction extends Operation {
+  @override
+  double execute(double a, double b) {
+    return a - b;
+  }
+}
+
+class Multiplication extends Operation {
+  @override
+  double execute(double a, double b) {
+    return a * b;
+  }
+}
+
+class Division extends Operation {
+  @override
+  double execute(double a, double b) {
+    if (b == 0) {
+      throw Exception('Division by zero is not allowed.');
+    }
+    return a / b;
+  }
+}
+
+class Power extends Operation {
+  @override
+  double execute(double a, double b) {
+    double result = 1;
+    for(int i = 0; i < b; i++) {
+      result *= a;
+    }
+    return result;
+  }
+}
+
+class Calculator {
+  final Map<String, dynamic> _operations = {};
+
+  void addOperation(String name, Operation operation) {
+    _operations[name] = operation;
+  }
+  double calculate(String name, double a, double b) {
+    final operation = _operations[name];
+    if (operation == null) {
+      throw ArgumentError('Operation $name not supported.');
+    }
+    return operation.execute(a,b);
+  }
+}
+
+void main () {
+  Calculator calculator = Calculator();
+
+  calculator.addOperation('addition', Addition());
+  calculator.addOperation('substraction', Subtraction());
+  calculator.addOperation('multiplication', Multiplication());
+  calculator.addOperation('division', Division());
+  calculator.addOperation('power', Power());
+
+  print(calculator.calculate('addition', 5, 3));
+  print(calculator.calculate('substraction', 6, 3));
+  print(calculator.calculate('multiplication', 5, 2));
+  print(calculator.calculate('division', 12, 6));
+  print(calculator.calculate('power', 2, 3));
+ 
+}