Duplicate carriage: Peak ticket
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Inputs
readings is a list of integers (numbers with no decimal part). It may be empty, and numbers may repeat unless task 1 says otherwise.
Your tasks
- Create a list
distinctSorted.readingsis already sorted from smallest to largest. Keep only one copy of each number. Put these numbers indistinctSortedin sorted order. - Find the largest number in
distinctSorted. Store it inlargest. - Complete
duplicateCarriagePeakTicketso it returnslargest. Return it, do not print it.
Example
If readings is [-1, 5, 6, 6, 11], then distinctSorted is [-1, 5, 6, 11] and duplicateCarriagePeakTicket returns 11.
Rules
- If
distinctSortedis empty, return 0. - If every number is negative, return the largest negative number. Do not replace it with 0.
Test data
TEST DATA 1: readings is [-12, 0, 5, 19, 19].
TEST DATA 2: readings is [-5, 8, 8, 8].
Examples
Input: readings = [-12,0,5,19,19] Output: 19
distinctSorted is [-12, 0, 5, 19]. The largest number is 19. Return 19.
Input: readings = [-5,8,8,8] Output: 8
distinctSorted is [-5, 8]. The largest number is 8. Return 8.
Input: readings = [] Output: 0
distinctSorted is []. The list is empty, so return 0.
Input limits
- 0 <= input size <= 50000.
- Answers fit in a signed 32-bit integer: -2,147,483,648 through 2,147,483,647.
- Input numbers have no decimal part. They range from -1,000,000 to 1,000,000. Follow any extra input rules in task 1.
Efficiency goal
Big-O describes how the work or memory needed grows as the input gets larger.
Efficiency goal: time O(n); extra memory, including the helper list, O(n). n is the input length. These labels describe how work and memory grow with the input.
Practice focus
Build distinctSorted first, then return exactly what the tasks ask for. Follow the order, keep repeated values when the rule says so, and check the empty case.