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                <p>Cliquez dans le carré plusieurs fois.</p>
<p id="vide"></p>


                #vide {
    font-size: 20px;
    width: 40px;
    height: 40px;
    border: solid thin red;
    text-align: center;



  Petit tour de magie que vous pouvez utiliser dans
  vos scripts: définit un alias $ pour document.querySelector
var $ = (s) => document.querySelector(s);

/* Un tableau bidimensionnel en JavaScript 
   est un tableau de tableaux 
   (en jargon, on parle plutôt de "liste de listes")
var tableau = Array(10);

for (var i = 0 ; i < 10 ; i++) {
    tableau[i] = Array(10);
    for (var j = 0 ; j < 10 ; j++) {
        tableau[i][j] = String.fromCharCode(i*10+j+35);

/* À chaque clic, on change le contenu de #vide */
var counter = 0;
$('#vide').addEventListener('click', function(e) {
    e.currentTarget.innerHTML = tableau[parseInt(counter / 10)][counter % 10];
    counter = counter + 1 % 100;
}, true);