
    Design an algorithm that determines the number of possible ways to organize writing assessment criteria into distinct feedback groups, where each criterion must be assigned to exactly one group and the order of elements within groups doesn't matter. Given n assessment criteria, calculate all possible grouping combinations to ensure comprehensive yet non-redundant feedback categories for student writing evaluation.
    

    
def bell_number(n):
    """
    Design an algorithm that determines the number of possible ways to organize writing assessment criteria into distinct feedback groups, where each criterion must be assigned to exactly one group and the order of elements within groups doesn't matter. Given n assessment criteria, calculate all possible grouping combinations to ensure comprehensive yet non-redundant feedback categories for student writing evaluation.
    

    """
def bell_number(n):
    """
    Design an algorithm that determines the number of possible ways to organize writing assessment criteria into distinct feedback groups, where each criterion must be assigned to exactly one group and the order of elements within groups doesn't matter. Given n assessment criteria, calculate all possible grouping combinations to ensure comprehensive yet non-redundant feedback categories for student writing evaluation.
    

    """
    bell = [[0 for i in range(n + 1)] for j in range(n + 1)]
    bell[0][0] = 1
    for i in range(1, n + 1):
        bell[i][0] = bell[i - 1][i - 1]
        for j in range(1, i + 1):
            bell[i][j] = bell[i - 1][j - 1] + bell[i][j - 1]
    return bell[n][0]