Sure! Below is the test case generator for the given problem "A: Cabbage":

```python
import random

def tcgen():
    # Define the constraints
    N = random.randint(1, 1000)  # 1 <= N <= 1000
    M = random.randint(0, N)  # 0 <= M <= N
    A = random.randint(1, 1000)  # 1 <= A <= 1000
    B = random.randint(A, 1000)  # A <= B <= 1000
    D = [random.randint(1, 1000) for _ in range(N)]  # List of N elements, each 1 <= D[i] <= 1000
    
    return N, M, A, B, D

def format_tc(N, M, A, B, D):
    input_data = f"{N} {M} {A} {B}\n" + " ".join(map(str, D))
    return input_data

# Generate a test case and format it
N, M, A, B, D = tcgen()
test_case = format_tc(N, M, A, B, D)
print(test_case)
```

This generator follows the constraints provided in the problem statement. It randomly generates values for \(N\), \(M\), \(A\), \(B\), and the list \(D\) within the specified ranges. The `format_tc` function formats the output to match the expected input format of the problem.

### Explanation of the Generator
- **N**: Number of leaves.
- **M**: Minimum number of leaves that should remain for cooking.
- **A**: Threshold for initial discard based on dirtiness.
- **B**: Threshold for reconsidering the discard based on dirtiness.
- **D**: List of dirtiness values for each leaf.

### Example Output

Running the provided script might output something like:

```
623 217 195 453
234 576 123 789 456 234 876 234 345 ...
```

This output can directly be used as an input for your problem to test various scenarios.