Square gauges: Positive-ink invoice
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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
roots. For each number x inreadings, find the largest whole number r whose square is at most x. A square means a number multiplied by itself. For example, x = 10 gives 3, because 3 * 3 = 9 but 4 * 4 = 16. Use whole-number comparisons, not rounded decimal square roots. Keep the answers in input order. - Add only the numbers in
rootsthat are greater than 0. Store the sum inpositiveTotal. - Complete
squareGaugesPositiveInkInvoiceso it returnspositiveTotal. Return it, do not print it.
Example
If readings is [9, 6, 5, 9, 5], then roots is [3, 2, 2, 3, 2] and squareGaugesPositiveInkInvoice returns 12.
Rules
- Skip zeros.
- If no number is greater than 0, return 0.
Test data
TEST DATA 1: readings is [18, 10, 18, 4, 0].
TEST DATA 2: readings is [7, 7, 7, 2].
Examples
Input: readings = [18,10,18,4,0] Output: 13
roots is [4, 3, 4, 2, 0]. Keep [4, 3, 4, 2] and add those numbers. Return 13.
Input: readings = [7,7,7,2] Output: 7
roots is [2, 2, 2, 1]. Keep [2, 2, 2, 1] and add those numbers. Return 7.
Input: readings = [] Output: 0
roots is []. Keep [] and add those numbers. 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 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 roots 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.