Untitled

<!DOCTYPE html>
<html>
<head>
  <title>Księga ocen</title>
  <style>
    /* Global styles */
    body {
      font-family: Arial, sans-serif;
      margin: 20px;
    }

    /* Table styles */
    table {
      border-collapse: collapse;
      width: 100%;
      border: 1px solid #ddd;
    }
    th, td {
      border: 1px solid #ddd;
      padding: 10px;
      text-align: left;
    }
    th {
      background-color: #f0f0f0;
    }
    tr:nth-child(even) {
      background-color: #f9f9f9;
    }

    /* Form styles */
    form {
      margin-bottom: 20px;
    }
    label {
      display: block;
      margin-bottom: 10px;
    }
    input[type="text"], input[type="number"] {
      width: 100%;
      padding: 10px;
      margin-bottom: 20px;
      border: 1px solid #ccc;
    }
    input[type="submit"] {
      background-color: #4CAF50;
      color: #fff;
      padding: 10px 20px;
      border: none;
      border-radius: 5px;
      cursor: pointer;
    }
    input[type="submit"]:hover {
      background-color: #3e8e41;
    }

    /* Header styles */
    h1 {
      font-size: 24px;
      margin-bottom: 10px;
    }
  </style>
</head>
<body>
  <h1>Księga ocen</h1>
  <form id="add-grade-form">
    <label for="student-name">Imię i nazwisko ucznia:</label>
    <input type="text" id="student-name" name="student-name"><br><br>
    <label for="grade">Ocena:</label>
    <input type="number" id="grade" name="grade"><br><br>
    <input type="submit" value="Dodaj ocenę">
  </form>
  <table id="grade-table">
    <thead>
      <tr>
        <th>Imię i nazwisko ucznia</th>
        <th>Oceny</th>
        <th>Średnia ocena</th>
      </tr>
    </thead>
    <tbody id="grade-table-body">
      <!-- oceny będą wyświetlane tutaj -->
    </tbody>
  </table>

  <script>
    // pobierz elementy tabeli i formularza
    const table = document.getElementById('grade-table');
    const form = document.getElementById('add-grade-form');
    const tbody = document.getElementById('grade-table-body');

    // utwórz obiekt do przechowywania ocen
    const grades = {};

    // dodaj event listener do formularza
    form.addEventListener('submit', (e) => {
      e.preventDefault();
      const studentName = document.getElementById('student-name').value;
      const grade = document.getElementById('grade').value;

      // dodaj ocenę do obiektu
      if (!grades[studentName]) {
        grades[studentName] = [];
      }
      grades[studentName].push(Number(grade));

      // zaktualizuj tabelę
      updateTable();
    });

    // funkcja do aktualizacji tabeli
    function updateTable() {
      tbody.innerHTML = '';
      Object.keys(grades).forEach((studentName) => {
        const gradesArray = grades[studentName];
        const averageGrade = calculateAverage(gradesArray);
        const row = document.createElement('tr');
        row.innerHTML = `
          <td>${studentName}</td>
          <td>${gradesArray.join(', ')}</td>
          <td>${averageGrade.toFixed(2)}</td>
        `;
        tbody.appendChild(row);
      });
    }

    // funkcja do obliczania średniej oceny
    function calculateAverage(gradesArray) {
      return gradesArray.reduce((a, b) => a + b, 0) / gradesArray.length;
    }
  </script>
</body>
</html>