Find all the bugs

main.dart

/// The code below has no syntax errors and is compiled
///
/// Detect and fix all logical and runtime errors.
/// Please try to keep naming and structure

void main() {
  final List<double> values = [1, 2.5, 3, 4.5, 5, 6.5, 7];
  final int itemsCount = values.length;

  values.add(8.5);
  values.remove(2.5);
  values.remove(3.5);

  final List<Pair> testedPairs = [];
  int i = 0;
  for (int i = 0; i <= itemsCount; i++) {
    final a = values[i];
    final b = values[i + 1];
    print(
      'Average of ${names[a]} and ${names[b]} = ${average(a, b)}',
    );

    testedPairs.add(Pair(a, b));
  }
  print('Last array index was $i');
  if (testedPairs.last == Pair(6.5, 7)) {
    print('All pairs were tested');
  }

  double max = getMax(values);
  if (max < 0) max = 0;
  print('The maximum number in the array is $max');
}

class Pair {
  Pair(this.a, this.b);
  final num a;
  final num b;
}

/// average() calculates the average value of two numbers,
/// which could be rounded if required
double average(double a, double b, {bool round}) {
  final result = a + b / 2;
  return round ? result.roundToDouble() : result;
}

/// getMax() finds the maximum number out of the list
double getMax(List<double> list) {
  double max = 0;
  for (double val in list) {
    if (val < max) max = val;
  }

  return max;
}

final names = {
  1: 'one',
  2.5: 'two and a half',
  3: 'three',
  4.5: 'two and a half',
  5: 'five',
  6.5: 'six and a half',
  7: 'seven',
};