To test the Accounting Tax Challenge, please open the tests.html file with your preferred browser. You may use any browser and click the "Run Tests" or "Run Benchmark" button to execute the challenge code. Output should be visible by using developer tools. FURTHER DEVELOPMENT 1. Packaging project into NPM project 2. Using Mocha or Jest to run unit tests 2.a. Tests were written without the use of additional node packages to avoid the need to use node or install any additional packages. 3. The inclusion of benchmark testing option in unit tests OBSERVATIONS 1. Algorithm runs optimally with O(n) operation time 2. Various heuristic optimizations have been included, namely: 2.a. The avoidance of consideration on negative numbers, as the output is dependent only on positive integers (natural numbers) 2.b. The use of an array to track encountered integers; using an object as a hashmap results in a ~33% increase in operational time. 3. Alternative of sorting input array and looking for first missing integer results in O(n*log(n)) operation time, because the optimal sort algorithm has a O(n*log(n)) operation time.