Javascript Quiz not working.. not errors

var questions = [
  ['Who was the first president of the United States', 'George Washington'],
  ['Who is the last historical Samurai to Japan?', 'Saigo Takamori'],
  ['How many legs does an insect have?', 6],
  ['How many megabites are in a gigabite', 1024],
  ['Name the largest star that is at the center of our galaxy', 'the Sun']

];


var correctAnswers = 0;
var question;
var answer;
var response;

var correct = [];
var wrong = [];


function print(message) {
  document.write(message);
  outputDiv.innerHTML = message;
}



function buildList(arr){
  var listHTML = '<ol>';

      for (var i = 0; i < arr.length; i +=1) {

          listHTML += '<li>' + arr[i] + '</li>';

      }  

  listHTML += '</ol>';

  return listHTML;

}




for (var i = 0; i < questions.length; i += 1) {

    question = questions[i][0];
    answer = questions[i][1];
    response = prompt(question);
    response = parseInt(response);

     if (response === answer) {
        correctAnswers += 1;
        correct.push(question); 
      }else{
        wrong.push(question);
      }

}




html = "You got " + correctAnswers + " question(s) right."
html += '<h2> You got these questions correct:</h2>';
html += buildList(correct);
html += '<h2>You got theses questions wrong:</h2>';
html += buildList(wrong);