times.js

function buildTimes() {
  var times = [];
  for (var i=-1;i<23;++i) {
    var idx = (i+1);
    var ampm = (idx>12 ? 'pm' : 'am');
    var time = (idx>12 ? idx%12 : (idx>0 ? idx : 12));
    if (idx==24) time = 12;
    var t = time + ':00' + ampm;
    times.push(t);
  }
  return times;
}