Input a list of positive numbers ( terminated by 0) into an array, find the mean ( average) of the numbers in the array, and output the result. Use a subprogram to input the numbers, a function to find the mean, and a sub-program to output the result.

To solve this problem, you can follow these steps:

1. Implement a subprogram to input the numbers into an array:
- Create an empty array to store the numbers.
- Start a loop to read numbers from the user until a zero is entered.
- Add each number to the array.
- Terminate the loop when a zero is entered.

2. Implement a function to find the mean (average) of the numbers in the array:
- Calculate the sum of all the numbers in the array.
- Divide the sum by the total number of elements in the array.
- Return the mean as the result.

3. Implement a subprogram to output the result:
- Invoke the mean calculation function to get the mean value.
- Print the mean value to the console.

Here's an example implementation in Python:

```python
def input_numbers():
numbers = []
while True:
num = int(input("Enter a positive number (0 to exit): "))
if num == 0:
break
numbers.append(num)
return numbers

def calculate_mean(numbers):
total = sum(numbers)
mean = total / len(numbers)
return mean

def output_result(mean):
print("The mean of the numbers is:", mean)

# Main program
numbers = input_numbers()
mean = calculate_mean(numbers)
output_result(mean)
```

In this example, the `input_numbers` function collects the numbers from the user and returns them as a list. The `calculate_mean` function calculates the average of the numbers using the `sum` function and the length of the list. Finally, the `output_result` function prints the mean to the console.

Note: The assumption here is that the user will only input positive numbers. Additional error handling can be added to the code if needed.

to find the average, just add up all the numbers and divide by how many there are.

That means you have to count them as you read them.