Priority basket: Even-key census
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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
removalOrder. Put all numbers fromreadingsinto a min-heap. A min-heap is a tree-shaped collection that keeps its smallest number at the top. Remove the smallest number, record it, and repeat until the heap is empty. Keep repeated numbers.removalOrderis the removal order. - Count the even numbers in
removalOrder. Store the count inevenCount. A number is even when it divides by 2 with no remainder. - Complete
priorityBasketEvenKeyCensusso it returnsevenCount. Return it, do not print it.
Example
If readings is [7, 7, 5, -2, 5], then removalOrder is [-2, 5, 5, 7, 7] and priorityBasketEvenKeyCensus returns 1.
Rules
- 0 and negative even numbers count too.
- If
removalOrderis empty, return 0.
Test data
TEST DATA 1: readings is [12, 0, -9, 12, 13].
TEST DATA 2: readings is [2, -5, 2, 2].
Examples
Input: readings = [12,0,-9,12,13] Output: 3
removalOrder is [-9, 0, 12, 12, 13]. The even numbers are [0, 12, 12]. There are 3, so return 3.
Input: readings = [2,-5,2,2] Output: 3
removalOrder is [-5, 2, 2, 2]. The even numbers are [2, 2, 2]. There are 3, so return 3.
Input: readings = [] Output: 0
removalOrder is []. The even numbers are []. There are 0, so return 0.
Input limits
- 0 <= input size <= 64.
- 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 log 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 removalOrder 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.