Project Euler/40

Champernowne's Constant

Problem Statement

An irrational decimal fraction is created by concatenating the positive integers:

$ 0.12345678910{\color{red}\mathbf 1}112131415161718192021\cdots $

It can be seen that the 12th digit of the fractional part is 1

If $ d_n $ represents the nth digit of the fractional part, find the value of the following expression.

$ d_1 \times d_{10} \times d_{100} \times d_{1000} \times d_{10000} \times d_{100000} \times d_{1000000} $

Solution

Project Euler/40/Solution