
    Write a function to calculate the ratio of unavailable delivery vehicles to active vehicles in a fleet's status array, where a value of 0 indicates an unavailable vehicle (due to maintenance, weather, or traffic) and any non-zero value represents an active vehicle. This ratio helps determine fleet utilization efficiency and assists in real-time route optimization decisions.
    

    
from array import array

def zero_count(nums):
    """
    Write a function to calculate the ratio of unavailable delivery vehicles to active vehicles in a fleet's status array, where a value of 0 indicates an unavailable vehicle (due to maintenance, weather, or traffic) and any non-zero value represents an active vehicle. This ratio helps determine fleet utilization efficiency and assists in real-time route optimization decisions.
    

    """
from array import array

def zero_count(nums):
    """
    Write a function to calculate the ratio of unavailable delivery vehicles to active vehicles in a fleet's status array, where a value of 0 indicates an unavailable vehicle (due to maintenance, weather, or traffic) and any non-zero value represents an active vehicle. This ratio helps determine fleet utilization efficiency and assists in real-time route optimization decisions.
    

    """
    n = len(nums)
    n1 = 0
    for x in nums:
        if x == 0:
            n1 += 1
        else:
            None
    return n1 / (n - n1)