040.js

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

// d_1 x d_10 x d_100 x d_1000 x d_10000 x d_100000 x d_1000000

function getProduct(zeroes) {
    let string = '';
    for (let i = 1; i <= 1000000; i++) {
        string += i;
    }
    let product = 1;
    for (let i = 0; i <= zeroes; i++) {
        product = product * parseInt(string[Math.pow(10, i) - 1], 10);
    }
    return product;
}


console.log( getProduct(6) );