<p>Design a <code>Calculator</code> 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 <code>Calculator</code> class constructor should accept a number which serves as the initial value of <code>result</code>.</p> <p>Your <font face="monospace"><code>Calculator</code> </font>class should have the following methods:</p> <ul> <li><code>add</code> - This method adds the given number <code>value</code> to the <code>result</code> and returns the updated <code>Calculator</code>.</li> <li><code>subtract</code> - This method subtracts the given number <code>value</code> from the <code>result</code> and returns the updated <code>Calculator</code>.</li> <li><code>multiply</code> - This method multiplies the <code>result</code> by the given number <code>value</code> and returns the updated <code>Calculator</code>.</li> <li><code>divide</code> - This method divides the <code>result</code> by the given number <code>value</code> and returns the updated <code>Calculator</code>. If the passed value is <code>0</code>, an error <code>"Division by zero is not allowed"</code> should be thrown.</li> <li><code>power</code> - This method raises the <code>result</code> to the power of the given number <code>value</code> and returns the updated <code>Calculator</code>.</li> <li><code>getResult</code> - This method returns the <code>result</code>.</li> </ul> <p>Solutions within <code>10<sup>-5</sup></code> of the actual result are considered correct.</p> <p> </p> <p><strong class="example">Example 1:</strong></p> <pre> <strong>Input:</strong> actions = ["Calculator", "add", "subtract", "getResult"], values = [10, 5, 7] <strong>Output:</strong> 8 <strong>Explanation:</strong> new Calculator(10).add(5).subtract(7).getResult() // 10 + 5 - 7 = 8 </pre> <p><strong class="example">Example 2:</strong></p> <pre> <strong>Input:</strong> actions = ["Calculator", "multiply", "power", "getResult"], values = [2, 5, 2] <strong>Output:</strong> 100 <strong>Explanation:</strong> new Calculator(2).multiply(5).power(2).getResult() // (2 * 5) ^ 2 = 100 </pre> <p><strong class="example">Example 3:</strong></p> <pre> <strong>Input:</strong> actions = ["Calculator", "divide", "getResult"], values = [20, 0] <strong>Output:</strong> "Division by zero is not allowed" <strong>Explanation:</strong> new Calculator(20).divide(0).getResult() // 20 / 0 The error should be thrown because we cannot divide by zero. </pre> <p> </p> <p><strong>Constraints:</strong></p> <ul> <li><code>actions</code> is a valid JSON array of strings</li> <li><code>values</code> is a valid JSON array of numbers</li> <li><code>2 <= actions.length <= 2 * 10<sup>4</sup></code></li> <li><code>1 <= values.length <= 2 * 10<sup>4</sup> - 1</code></li> <li><code>actions[i]</code> is one of "Calculator", "add", "subtract", "multiply", "divide", "power", and "getResult"</li> <li>First action is always "Calculator"</li> <li>Last action is always "getResult"</li> </ul>