<meta charset="UTF-8">
<input/>
<button>Compare</button>
<script>
var segredo = Math.round(Math.random()*10);
var input = document.querySelector("input");
input.focus();
function verifica() {
if (input.value == segredo) {
alert("ACERTOU");
} else {
alert("ERROU");
}
input.value = "";
input.focus();
}
var button = document.querySelector("button");
button.onclick = verifica;
</script>
