Mi código con arrays | Lógica de programación: Conceptos primordiales

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta http-equiv="X-UA-Compatible" content="IE=edge" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Secreto</title>
    <h1>SECRETO</h1>
  </head>
  <body>
    <input placeholder="Digite numero aqui" />
    <button>Comprobar número secreto</button>
    <script>
      var secretNumber = [3, 4, 5, 7],
        input1 = document.querySelector("input");
      input1.focus();

      function verificar() {
        encontrado = false;
        for (let position = 0; position < 4; position++) {
          if (parseInt(input1.value) == secretNumber[position]) {
            alert("Es correcto");
            encontrado = true;
            break;
          };
        };
        input1.value = "";
        input1.focus();
        if (encontrado == false) {
          alert("Incorreto");
        };
      };
      let button = document.querySelector("button");
      button.onclick = verificar;
    </script>
  </body>
</html>