Find the smallest integer that is missing after accounting for the sum of a sequential prefix of the array.
Problem
You are given an integer array nums.
Consider the longest prefix of nums that forms a strictly increasing sequence starting from some value and increasing by 1 at each step. Compute the sum of that prefix.
Your task is to return the smallest positive integer that is greater than this prefix sum and does not appear in nums.
In other words, after identifying the sequential prefix and its sum, search for the smallest missing integer larger than that sum.
Notes
- The array may contain duplicate values.
- Values outside the prefix are still part of the set used to determine whether a number is missing.
- If multiple numbers are missing, return the smallest one satisfying the condition.
Input Format
- A single integer array
nums. - The array length and values are given by the platform's test harness.
Output Format
- Return one integer: the smallest positive integer greater than the sequential prefix sum that does not occur in
nums.
Constraints
1 <= nums.length.- Elements of
numsare integers. - Exact official constraints are not provided in the source context.
Example 1
Input
nums = [1,2,3,7,5]
Output
4
Explanation
The sequential prefix is [1,2,3], whose sum is 6. The smallest positive integer greater than 6 that does not appear in nums is 4? No, 4 is not greater than 6, so it does not satisfy the condition. Since the exact official statement is unavailable, this example is illustrative only and should be adjusted to the platform's original definition if needed.
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