Ramanujan's Magic Square

magicSquare.js

function magicSquare(date) {
  date = date instanceof Date ? date : new Date(date);
  var d = date.getDate(),
    m = date.getMonth() + 1,
    c = ~~(date.getFullYear() / 100),
    y = date.getFullYear() % 100;
  return [
    [d, m, c, y],
    [y + 1, c - 1, m - 3, d + 3],
    [m - 2, d + 2, y + 2, c - 2],
    [c + 1, y - 1, d + 1, m - 1]
  ];
}

/**
 * Example:
 * magicSquare(new Date(1994, 4, 1));
 * 
 * Output:
 * [
 *   [1, 5, 19, 94],
 *   [95, 18, 2, 4],
 *   [3, 3, 96, 17],
 *   [20, 93, 2, 4]
 * ];
 */