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Counting Every Occurrence of the Digit 1 — drill-1 — LearnYard

03 Dsa FundamentalsMath BasicsCount the Total Occurrences of the Digit '1' in All Positive Integers Less than or Equal to a Given Integer n

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DSA FUNDAMENTALS › MATH BASICS

Write it, run it, read the output

Reading · 5 minQuiz · 5 questions2 code drills · run only

This is a scratch drill — your code runs, nothing is graded or recorded. No test cases, no expected output, no verdict.

TASK

Using n = 13, count every occurrence of the digit 1 in all integers from 1 through n. Print the total, which must be 6.

C++

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OUTPUT

Sample

What a finished answer prints, from the lesson. Nothing has run yet — press Run and this is replaced by your program’s own output.

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