jquery change picture onclick

1<!-- https://codepen.io/poliweb/pen/eYJNqLM -->
2<!-- https://stackoverflow.com/questions/26377231/jquery-how-to-change-img-src-path-onclick -->
3
4<div class="img-container">
5  <img id="changeMe" src="">
6</div>
7
8<img class="preview" src="images/preview-1.jpg">
9<img class="preview" src="images/preview-2.jpg">
10<img class="preview" src="images/preview-2.jpg">
11  
12 <!-- Script --> 
13  
14  $('.preview').on('click',  function() {
15    $('#changeMe').prop('src', this.src);
16});
17

1// https://codepen.io/kman/pen/dXjpoX
2// Stockphotos JS
3
4$(document).ready(function(){
5  var flag = 0;  
6  $("button#changeSize").click(function(){
7    if(flag == 0) {
8      $("#dummyimage").attr("src","http://dummyimage.com/350x155/");
9      flag = 1;
10    }
11    else if(flag == 1) {
12      $("#dummyimage").attr("src","http://dummyimage.com/450x255/");
13      flag = 0;
14    }
15  });
16});