Counting Ones

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CodePlex - Pramana 2018 Problem description. This program is a fun math problem! Consider a function f (n) that takes a positive integer n and returns the number of 1's in the decimal representation of all the integers from 0 to n, inclusive. For example, f(13) = 6, for the numbers 1, 10, 11 (twice, for two 1s), 12 and 13. Notice that f (1) = 1. Your task is to write a program that calculates f

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solution.cppC++17

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