Bit ribbons: Threshold file
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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
oneCounts. Write each number inreadingsin binary, the number system that uses only 0 and 1. Count the 1s in that form. For example, 5 is 101 in binary, so its count is 2. The count for 0 is 0. Put the counts in input order. - Count the numbers in
oneCountsthat are at leastk(greater than or equal tok). Store the count inatLeastK. - Complete
bitRibbonsThresholdFileso it returnsatLeastK. Return it, do not print it.
Example
If readings is [1, 3, 1, 3, 7] and k is 1, then oneCounts is [1, 2, 1, 2, 3] and bitRibbonsThresholdFile returns 5.
Rules
- If
oneCountsis empty, the count is 0. k(a whole number from 1 to 8) is the threshold in task 2: compare each number with it.
Test data
TEST DATA 1: readings is [9, 0, 12, 12, 16] and k is 6.
TEST DATA 2: readings is [6, 6, 2, 6] and k is 4.
Examples
Input: readings = [9,0,12,12,16] k = 6 Output: 0
oneCounts is [2, 0, 2, 2, 1]. Here k is 6. The numbers at least 6 are []. There are 0, so return 0.
Input: readings = [6,6,2,6] k = 4 Output: 0
oneCounts is [2, 2, 1, 2]. Here k is 4. The numbers at least 4 are []. There are 0, so return 0.
Input: readings = [] k = 2 Output: 0
oneCounts is []. Here k is 2. The numbers at least 2 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 are whole numbers from 0 through 1000000.
Efficiency goal
Big-O describes how the work or memory needed grows as the input gets larger.
Efficiency goal: time O(n log M); extra memory, including the helper list, O(n). n is the input length; M is the largest input number. These labels describe how work and memory grow with the input.
Practice focus
Build oneCounts 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.