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<html>
<head>
  <meta charset="utf-8">
  <title>JS Star Pattern 9 - Try It (Helper)</title>
</head>
<body>
  <h1>Hollow Diamond (printRow Helper)</h1>
  <p>Edit the row count or helper, then click Run.</p>
  <pre id="output" style="font-family: monospace; white-space: pre;"></pre>
  <script>
    function printRow(i, rows) {
      let line = "";
      for (let j = rows; j >= 1; j--) {
        line += i === j ? "*" : " ";
      }
      for (let k = 2; k <= rows; k++) {
        line += i === k ? "*" : " ";
      }
      return line;
    }

    let rows = 5;
    let result = "";

    for (let i = 1; i <= rows; i++) {
      result += printRow(i, rows) + "\n";
    }
    for (let i = rows - 1; i >= 1; i--) {
      result += printRow(i, rows) + "\n";
    }

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

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JavaScript Star Pattern 9 (Try It - Helper)