Leetcode Problem 163. Missing Ranges

Algorithm

1. Initialize a list missingRanges to store the missing ranges.
2. Check if nums is empty. If it is, add the range [lower, upper] to missingRanges and return it.
3. If lower is less than the first element of nums, add the range [lower, nums[0] - 1] to missingRanges.
4. Iterate over the elements of nums from the first to the second-to-last element:
   • If the difference between the current element and the next element is greater than 1, add the range [current element + 1, next element - 1] to missingRanges.
5. After the loop, if upper is greater than the last element of nums, add the range [nums[-1] + 1, upper] to missingRanges.
6. Return the list missingRanges.