var chapter_list = new Array(
  ["Vol.01 Ch.001: The Mad Tea Party","v01/c001"],
  ["Vol.01 Ch.002: The Little Crooked House part 1","v01/c002"],
  ["Vol.01 Ch.003: The Little Crooked house part 2","v01/c003"],
  ["Vol.01 Ch.004: Black Sheep","v01/c004"],
  ["Vol.01 Ch.005","v01/c005"],
  ["Vol.01 Ch.006","v01/c006"],
  ["Vol.02 Ch.001","v02/c001"],
  ["Vol.02 Ch.002","v02/c002"],
  ["Vol.02 Ch.003","v02/c003"],
  ["Vol.02 Ch.004","v02/c004"],
  ["Vol.02 Ch.005: Bloodberry Jam","v02/c005"],
  ["Vol.02 Ch.006: Lion Crest","v02/c006"],
  ["Vol.03 Ch.000","v03/c000"],
  ["Vol.04 Ch.000","v04/c000"],
  ["Vol.05 Ch.000","v05/c000"],
  ["Vol.06 Ch.000","v06/c000"],
  ["Vol.07 Ch.000","v07/c000"],
  ["Vol.08 Ch.001","v08/c001"],
  ["Vol.08 Ch.002","v08/c002"],
  ["Vol.08 Ch.003","v08/c003"],
  ["Vol.08 Ch.004","v08/c004"],
  ["Vol.08 Ch.005","v08/c005"],
  ["Vol.08 Ch.006: End","v08/c006"]
);

var total_chapters = 23;

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;