var chapter_list = new Array(
  ["Vol.01 Ch.001: Opening","v01/c001"],
  ["Vol.01 Ch.002: Wanted","v01/c002"],
  ["Vol.01 Ch.003: Noise","v01/c003"],
  ["Vol.01 Ch.004: Circus","v01/c004"],
  ["Vol.01 Ch.005: Black Sheep","v01/c005"],
  ["Vol.01 Ch.006: Hide & Seek + Extras","v01/c006"],
  ["Vol.02 Ch.007: Tears","v02/c007"],
  ["Vol.02 Ch.008: Your Body","v02/c008"],
  ["Vol.02 Ch.009: Research Tower","v02/c009"],
  ["Vol.02 Ch.010: Niji Forest","v02/c010"],
  ["Vol.02 Ch.011: Eva","v02/c011"],
  ["Vol.02 Ch.012: In Karasuna + Extras","v02/c012"],
  ["Vol.03 Ch.013: Flightless Wings","v03/c013"],
  ["Vol.03 Ch.014: Look at the Sky!","v03/c014"],
  ["Vol.03 Ch.015: Mermaid's Bottle","v03/c015"],
  ["Vol.03 Ch.016: Rinoll","v03/c016"],
  ["Vol.03 Ch.017: Lost Yukkin","v03/c017"],
  ["Vol.03 Ch.018: Conflict + Extras","v03/c018"],
  ["Vol.04 Ch.019: Oath","v04/c019"],
  ["Vol.04 Ch.020: Small Voices","v04/c020"],
  ["Vol.04 Ch.021: First Ship","v04/c021"],
  ["Vol.04 Ch.022: Unique Environment","v04/c022"],
  ["Vol.04 Ch.023: Gentle Person","v04/c023"],
  ["Vol.04 Ch.024: Your Own Place","v04/c024"],
  ["Vol.05 Ch.025: Vantnam","v05/c025"],
  ["Vol.05 Ch.026: Yanari","v05/c026"],
  ["Vol.05 Ch.027: Kidnapping","v05/c027"],
  ["Vol.05 Ch.028: A Warm Home","v05/c028"],
  ["Vol.05 Ch.029: Unsolvable Formula","v05/c029"],
  ["Vol.05 Ch.030: Decision","v05/c030"],
  ["Vol.05 Ch.030.5: EMPLOYING A PRINCESS","v05/c030.5"]
);

var total_chapters = 31;

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;