var chapter_list = new Array(
  ["Vol.01 Ch.001: Bad Company â‘ ","v01/c001"],
  ["Vol.01 Ch.002: Bad Company â‘¡","v01/c002"],
  ["Vol.01 Ch.003: Bad Company â‘¢","v01/c003"],
  ["Vol.01 Ch.004: Bad Company â‘£","v01/c004"],
  ["Vol.01 Ch.005: Bad Company 2 â‘ ","v01/c005"],
  ["Vol.01 Ch.006: Bad Company 2 â‘¡","v01/c006"],
  ["Vol.01 Ch.007: Bad Company 2 â‘¢","v01/c007"],
  ["Vol.01 Ch.008: Bad Company 2 â‘£","v01/c008"],
  ["Vol.01 Ch.009: Bad Company 2 ⑤","v01/c009"],
  ["Vol.01 Ch.010: Bad Company 2 â‘¥","v01/c010"]
);

var total_chapters = 10;

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;