var chapter_list = new Array(
  ["Vol.01 Ch.001: The Girl and the Sea","v01/c001"],
  ["Vol.01 Ch.002: Yumegaoka High","v01/c002"],
  ["Vol.01 Ch.003: School Life","v01/c003"],
  ["Vol.01 Ch.004: A Path in the Air","v01/c004"],
  ["Vol.01 Ch.005: Cherry Blossom Path","v01/c005"],
  ["Vol.01 Ch.006: Dotty and Pikari","v01/c006"],
  ["Vol.01 Ch.007: Roadside Station","v01/c007"],
  ["Vol.01 Ch.008: Pool Training","v01/c008"],
  ["Vol.01 Ch.009: Springtime Murkiness","v01/c009"],
  ["Vol.01 Ch.010: Meeting Again","v01/c010"],
  ["Vol.01 Ch.011: Meeting","v01/c011"],
  ["Vol.01 Ch.012: Treasure","v01/c012"],
  ["Vol.01 Ch.013: Into the Rainy Season","v01/c013"],
  ["Vol.01 Ch.013.5: Extra: The Daily Life of a Certain Advisor","v01/c013.5"],
  ["Vol.02 Ch.014: Dotty and a Lecture","v02/c014"],
  ["Vol.02 Ch.015: Love Letter","v02/c015"],
  ["Vol.02 Ch.016: Abadoned Cat","v02/c016"],
  ["Vol.02 Ch.017: Towards the Azure Sea","v02/c017"],
  ["Vol.02 Ch.018: The Sea's Blessing","v02/c018"],
  ["Vol.02 Ch.019: Daruma","v02/c019"],
  ["Vol.02 Ch.020: Closing Ceremony","v02/c020"],
  ["Vol.02 Ch.021: Choice","v02/c021"]
);

var total_chapters = 22;

for (var i = 0; i < chapter_list.length; i++) {
  document.getElementById('top_chapter_list').options[i] = new Option(chapter_list[i][0], chapter_list[i][1]);
  document.getElementById('bottom_chapter_list').options[i] = new Option(chapter_list[i][0], chapter_list[i][1]);
}
document.getElementById('top_chapter_list').value=current_chapter;
document.getElementById('bottom_chapter_list').value=current_chapter;
var current_chapter_index = document.getElementById('top_chapter_list').selectedIndex;