Design a Calculator class. The class should provide the mathematical operations of addition, subtraction, multiplication, division, and exponentiation. It should also allow consecutive operations to be performed using method chaining. The Calculator class constructor should accept a number which serves as the initial value of result.
Your Calculator class should have the following methods:
add - This method adds the given number value to the result and returns the updated Calculator.subtract - This method subtracts the given number value from the result and returns the updated Calculator.multiply - This method multiplies the result by the given number value and returns the updated Calculator.divide - This method divides the result by the given number value and returns the updated Calculator. If the passed value is 0, an error "Division by zero is not allowed" should be thrown.power - This method raises the result to the power of the given number value and returns the updated Calculator.getResult - This method returns the result.Solutions within 10-5 of the actual result are considered correct.
Example 1:
Input: actions = ["Calculator", "add", "subtract", "getResult"], values = [10, 5, 7] Output: 8 Explanation: new Calculator(10).add(5).subtract(7).getResult() // 10 + 5 - 7 = 8
Example 2:
Input: actions = ["Calculator", "multiply", "power", "getResult"], values = [2, 5, 2] Output: 100 Explanation: new Calculator(2).multiply(5).power(2).getResult() // (2 * 5) ^ 2 = 100
Example 3:
Input: actions = ["Calculator", "divide", "getResult"], values = [20, 0] Output: "Division by zero is not allowed" Explanation: new Calculator(20).divide(0).getResult() // 20 / 0 The error should be thrown because we cannot divide by zero.
Constraints:
actions is a valid JSON array of stringsvalues is a valid JSON array of numbers2 <= actions.length <= 2 * 1041 <= values.length <= 2 * 104 - 1actions[i] is one of "Calculator", "add", "subtract", "multiply", "divide", "power", and "getResult"In this approach, we will design a Calculator class with a constructor that initializes the result. Each operation method will modify the object's state and return the Calculator object itself to allow method chaining. The method for division needs to handle division by zero gracefully by throwing an appropriate exception.
In the Python solution, each method modifies self.result, a class attribute, and returns self to allow method chaining. The divide method checks for division by zero and raises a ValueError if encountered. The getResult() method returns the current result.
Java
Time Complexity: O(1) for each operation since they all perform a constant amount of work.
Space Complexity: O(1) since we use only a fixed amount of space irrespective of input size.
This approach emphasizes clear error management alongside method chaining. Each mathematical function adjusts the internal result and returns the instance for seamless operation chaining. Special attention is paid to division, where an exception is thrown in case of dividing by zero, ensuring the program handles this gracefully.
In the JavaScript implementation, each operation method updates the result attribute and returns the current instance to enable method chaining. The divide method checks for zero to prevent division by zero, throwing an Error as appropriate. The method getResult retrieves the current value of result.
C#
Time Complexity: O(1) for each operation; each involves direct arithmetic with a constant time overhead.
Space Complexity: O(1) due to constant space usage regardless of input size.
| Approach | Complexity |
|---|---|
| Class Design with Method Chaining | Time Complexity: O(1) for each operation since they all perform a constant amount of work. |
| Fluent Interface with Error Handling | Time Complexity: O(1) for each operation; each involves direct arithmetic with a constant time overhead. |
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