var chapter_list = new Array(
  ["Vol.01 Ch.001: Invade","v01/c001"],
  ["Vol.01 Ch.002: Fei Mei","v01/c002"],
  ["Vol.01 Ch.003: Man of the Lost Soul","v01/c003"],
  ["Vol.01 Ch.004: First Defeat","v01/c004"],
  ["Vol.01 Ch.005: Transformation","v01/c005"],
  ["Vol.01 Ch.006: Momiji","v01/c006"],
  ["Vol.01 Ch.007: Assassin from Feng","v01/c007"],
  ["Vol.01 Ch.008: Dirt","v01/c008"],
  ["Vol.02 Ch.009: Yin + Yang","v02/c009"],
  ["Vol.02 Ch.010: Dead End","v02/c010"],
  ["Vol.02 Ch.011: Encounters with the Destroyer - Part 1","v02/c011"],
  ["Vol.02 Ch.012: Encounters with the Destroyer - Part 2","v02/c012"],
  ["Vol.02 Ch.013: I Only Wish to Ask About One Thing","v02/c013"],
  ["Vol.02 Ch.014: That Day","v02/c014"],
  ["Vol.02 Ch.015: Counterstrike","v02/c015"],
  ["Vol.02 Ch.016: Retreat","v02/c016"],
  ["Vol.02 Ch.017: Sacrifice","v02/c017"],
  ["Vol.02 Ch.017.5: Blue Seed Drafts","v02/c017.5"]
);

var total_chapters = 18;

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;