Notice: This page requires JavaScript to function properly.
Please enable JavaScript in your browser settings or update your browser.

book
Ordinary Numbers

A positive integer n is called ordinary if all its digits in decimal notation are the same. For example, 1, 2, and 99 are ordinary numbers, while 719 and 2021 are not.

Given a number n, count how many ordinary numbers exist between 1 and n.

Example 1

Input:

100

Output:

18

Example 2

Input:

5

Output:

5
main.cpp

main.cpp

C++

Kysy tekoälyä

expand

Kysy tekoälyä

ChatGPT

Kysy mitä tahansa tai kokeile jotakin ehdotetuista kysymyksistä aloittaaksesi keskustelumme

some-alt