Fixed panels: 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
windowSums. A window is a group of numbers next to each other. Take each window of exactlyknumbers inreadings, moving one place right each time. Record each window sum from left to right. If the whole input has fewer thanknumbers,windowSumsis empty. - Count the even numbers in
windowSums. Store the count inevenCount. A number is even when it divides by 2 with no remainder. - Complete
fixedPanelsEvenKeyCensusso it returnsevenCount. Return it, do not print it.
Example
If readings is [4, 2, 4, 4, -9] and k is 8, then windowSums is [] and fixedPanelsEvenKeyCensus returns 0.
Rules
- 0 and negative even numbers count too.
- If
windowSumsis empty, return 0. k(a whole number from 1 to 8) is the window size in task 1.
Test data
TEST DATA 1: readings is [8, 0, -6, 16, 8] and k is 5.
TEST DATA 2: readings is [-8, 5, 5, 5] and k is 8.
Examples
Input: readings = [8,0,-6,16,8] k = 5 Output: 1
windowSums is [26]. The even numbers are [26]. There are 1, so return 1.
Input: readings = [-8,5,5,5] k = 8 Output: 0
windowSums is []. The even numbers are []. There are 0, so return 0.
Input: readings = [] k = 7 Output: 0
windowSums is []. The even numbers are []. There are 0, so return 0.
Input limits
- 0 <= input size <= 64.
- k is a whole number from 1 to 8. 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 windowSums 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.