HTML Code

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JS Alphabet Pattern 34 - Try It</title>
</head>
<body>
  <h1>Alphabet diamond</h1>
  <p>Edit <code>top</code> or the blank character, then click Run.</p>

  <pre id="output"></pre>

  <script>
    (() => {
      const A = "A".charCodeAt(0);
      const top = "E".charCodeAt(0);

      function row(i) {
        let line = "";
        for (let j = top; j >= A; j--) line += (i === j ? String.fromCharCode(j) : " ");
        for (let k = A + 1; k <= top; k++) line += (i === k ? String.fromCharCode(k) : " ");
        return line;
      }

      let result = "";
      for (let i = A; i <= top; i++) result += row(i) + "\n";
      for (let i = top - 1; i >= A; i--) result += row(i) + "\n";

      document.getElementById("output").textContent = result;
    })();
  </script>
</body>
</html>

Lines: 0 | Characters: 0

Live Preview Auto-refresh on Run

JavaScript Alphabet Pattern 34 (Try It)