Project Euler 19 - Counting Sundays - Solved with JavaScript

The 19th Project Euler problem - Counting Sundays - is stated as follows. How many Sundays fell on the first of the month during the twentieth century (1 Jan 1901 to 31 Dec 2000)?

// Get all the months between Jan 1901 to Dec 2000.
// We add 12 since we want the months in 2000 as well.
const months = (2000 - 1901) * 12 + 12;

// Iterate one month at a time.
const sundays = Array.from({length:months})
  .filter((_,month) => {
    const currentYear = 1901 + Math.floor(month/12);
    const currentMonth = month % 12;
    // Check the weekday of the 1 in the current year and month.
    // 0 equals Sunday.
    return new Date(currentYear, currentMonth, 1).getDay() === 0
  }).length;

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