Implement an Instance Method to Update State

Summary

Practice writing an instance method that mutates an object's state and returns the updated value.

Problem statement

You are given a simple Counter class that keeps an integer value. Implement the instance method increment(self, amount) which adds the given amount to the counter's value, updates the instance state, and returns the updated value. The constructor accepts an optional starting value (default 0). The method should accept positive, zero, and negative integers.

Task

Implement the Counter.increment method so it updates the instance's value and returns the new value.

Examples

Input format

A call to Counter(start).increment(amount) where start is optional integer and amount is an integer.

Output format

An integer representing the updated counter value (returned by the increment method).

Constraints

- start and amount will be integers (may be negative or zero). - The increment method should mutate self.value and return the new integer value.

Samples