var array = [
 {
   id: 1,
   unit: '1A',
   division: 1
 },
  {
   id: 2,
   unit: '2A',
   division: 1
 },
  {
   id: 3,
   unit: '3A',
   division: 1
 },
  {
   id: 4,
   unit: '4A',
   division: 1
 },
   {
   id: 5,
   unit: '5A',
   division: 1
 },
  {
   id: 6,
   unit: '6A',
   division: 1
 },
  {
   id: 7,
   unit: '1A',
   division: 2
 },
  {
   id: 8,
   unit: '1B',
   division: 2
 },
  {
   id: 9,
   unit: '2A',
   division: 2
 },
  {
   id: 10,
   unit: '2B',
   division: 2
 },
   {
   id: 11,
   unit: '3A',
   division: 2
 },
  {
   id: 12,
   unit: '3B',
   division: 2
 }
];

var division = [];
var divs     = '';

for(var i in array){
   division.push(array[i].division);
}

division = unique(division);

for(var k in division){
  for(var j in array){
     if(division[k] == array[j].division){
        if(array[j].unit % 2 == 0){
           divs += '<div class="unit">'+array[j].unit+'</div>';
        }else{
           divs += '<div class="unit">'+array[j].unit+'</div>';
        }
     }
  }
}