Implement Plus One

Given a non-empty array of digits representing a non-negative integer, where the most significant digit comes first and each element is in [0, 9], add one to the integer and return the resulting array of digits. You may not convert the entire array directly into a built-in big integer. Examples: - [1, 2, 3] -> [1, 2, 4] - [4, 3, 2, 1] -> [4, 3, 2, 2] - [9, 9, 9] -> [1, 0, 0, 0] Discuss the time and space complexity of your approach.