index.html
<style>
  .row {
    display:flex;
    align-items:center;
  }
  .cell {
    height:13vmin;
    border:thin solid;
  }
</style>
<script src='one_row.js'></script>
<script src='cell_clicked.js'></script>
<div class='row'>
  <script>one_row();</script>
</div>
one_row.js
function one_row() {
  var s1=" <img src='counters/0.png' class='cell' id='";
  var s2="' cn='0' onClick='cell_clicked(this);'>";
  for (var i=0; i<5; i++) {
    document.write(s1 + i + s2);
  }
  document.write('<div>0</div>');
}
cell_clicked.js
function cell_clicked(image) {
  image.src='counters/1.png';
  image.setAttribute('cn','1');
}