Missing Elements in Sequence (Easy) — Practice with Code Visualizer

You are given an integer array nums containing n elements, where each element is a positive integer in the range [1, n]. Some numbers appear more than once, while one or more numbers in the expected range are missing entirely.

Your task is to identify and return a list of all integers from 1 to n (inclusive) that are not present in the array. The returned values should be in ascending order.

Key Observations:

The array length determines the range of expected values: if the array has n elements, you're looking for missing values among 1, 2, 3, ..., n.
Since values repeat, the count of missing elements equals the count of duplicates.
Each missing element should appear exactly once in your output.

The array has 8 elements, so we expect all integers from 1 to 8. The values 5 and 6 are absent, while 2 and 3 are duplicated. Thus, [5, 6] are the missing elements.

With 2 elements, we expect values 1 and 2. The value 1 appears twice, but 2 is missing. The result is [2].

Both values 1 and 2 are present in this 2-element array, so no values are missing. Return an empty array.

Your task is to identify and return a list of all integers from 1 to n (inclusive) that are not present in the array. The returned values should be in ascending order.

Key Observations:

The array length determines the range of expected values: if the array has n elements, you're looking for missing values among 1, 2, 3, ..., n.
Since values repeat, the count of missing elements equals the count of duplicates.
Each missing element should appear exactly once in your output.

The array has 8 elements, so we expect all integers from 1 to 8. The values 5 and 6 are absent, while 2 and 3 are duplicated. Thus, [5, 6] are the missing elements.

With 2 elements, we expect values 1 and 2. The value 1 appears twice, but 2 is missing. The result is [2].

Both values 1 and 2 are present in this 2-element array, so no values are missing. Return an empty array.

Missing Elements in Sequence

Hints

Missing Elements in Sequence

Hints