var chapter_list = new Array(
  ["Vol.01 Ch.001: Let's Play Pingpong?","v01/c001"],
  ["Vol.01 Ch.002: The Long Stairs to the Table, part 1","v01/c002"],
  ["Vol.01 Ch.003: The Long Stairs to the Table, part 2","v01/c003"],
  ["Vol.01 Ch.004: Contact with Ohka","v01/c004"],
  ["Vol.01 Ch.005: Doubles","v01/c005"],
  ["Vol.01 Ch.006: Desperation","v01/c006"],
  ["Vol.01 Ch.007: Each One of the Three with His Losing","v01/c007"],
  ["Vol.02 Ch.008: At the End of Spring","v02/c008"],
  ["Vol.02 Ch.009: The Third Man","v02/c009"],
  ["Vol.02 Ch.010: Monster","v02/c010"],
  ["Vol.02 Ch.011: Ohka High","v02/c011"],
  ["Vol.02 Ch.012: Respective Reunion","v02/c012"],
  ["Vol.02 Ch.013: Mashiro's Rage","v02/c013"],
  ["Vol.02 Ch.014: Different World","v02/c014"],
  ["Vol.02 Ch.015: Mashiro's Fight","v02/c015"],
  ["Vol.02 Ch.016: A Pretty Empty","v02/c016"]
);

var total_chapters = 16;

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;