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Project Euler #40: Champernowne's constant

Question
An irrational decimal fraction is created by concatenating the positive integers:
0.123456789101112131415161718192021...
It can be seen that the 12th digit of the fractional part is 1.
If dn represents the nth digit of the fractional part, find the value of the following expression.
d1 × d10 × d100 × d1000 × d10000 × d100000 × d1000000

Answer :

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Solution 
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import java.util.Scanner;

public class Solution {

    private static int getDigit(long x) {
        int digits = 1;
        long range = 9;
        long first = 1;
        long skip = 0;
        while(skip + digits * range < x) {
            skip += digits * range;
            digits++;
            range *= 10;
            first *= 10;
        }
        while(range > 0) {
            while(skip + digits * range < x) {
                skip += digits * range;
                first += range;
            }
            range /= 10;
        }
        while(skip + digits < x) {
            first++;
            skip += digits;
        }
        x -= skip;
        x--;
        char s = String.valueOf(first).charAt((int) x);
        return s - '0';
    }

    public static void main(String[] args) {
        try(Scanner sc = new Scanner(System.in)) {
            int T = sc.nextInt();
            while(T-- > 0) {
                int product = 1;
                for(int i = 0; i < 7; i++) {
                    long pos = sc.nextLong();
                    product *= getDigit(pos);
                }
                System.out.println(product);
            }
        }
    }
}
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