# Spot the bug: Flutter

> One snippet. Find the bug, or prove there isn't one.

Daily challenge: 2026-08-19 (UTC) · Mid-Level

```dart
class PriceCalculator {
  List<double> applyDiscount(List<double> prices, double discount) {
    for (int i = 0; i < prices.length; i++) {
      prices[i] = prices[i] * (1 - discount);
    }
    return prices;
  }
}

void main() {
  final original = [10.0, 20.0, 30.0];
  final calc = PriceCalculator();
  final discounted = calc.applyDiscount(original, 0.1);
  print(original);
}
```

## Your verdict

- Security flaw
- Logic bug
- Code style
- No issue

One attempt per day. The answer shows up right after.

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