
    Determine the number of different ways to group parking zones in a city into distinct pricing categories, where each zone must be assigned to exactly one pricing category, and any number of pricing categories can be created. The goal is to calculate all possible pricing structure combinations that could be implemented across n parking zones, where each possible grouping represents a unique way to organize parking rates throughout the city.
    

    
def bell_number(n):
    """
    Determine the number of different ways to group parking zones in a city into distinct pricing categories, where each zone must be assigned to exactly one pricing category, and any number of pricing categories can be created. The goal is to calculate all possible pricing structure combinations that could be implemented across n parking zones, where each possible grouping represents a unique way to organize parking rates throughout the city.
    

    """
def bell_number(n):
    """
    Determine the number of different ways to group parking zones in a city into distinct pricing categories, where each zone must be assigned to exactly one pricing category, and any number of pricing categories can be created. The goal is to calculate all possible pricing structure combinations that could be implemented across n parking zones, where each possible grouping represents a unique way to organize parking rates throughout the city.
    

    """
    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]