Python: Count the number of groups of non-zero numbers separated by zeros of a given list of numbers

Python List: Exercise - 209 with Solution

Write a Python program to count the number of groups of non-zero numbers separated by zeros in a given list of numbers.

Sample Solution:

Python Code:

def test(lst):
    previous_digit = 0
    ctr = 0
    for digit in lst:
        if previous_digit==0 and digit!=0:
            ctr+=1
        previous_digit = digit
    return ctr

nums = [3,4,6,2,0,0,0,0,0,0,6,7,6,9,10,0,0,0,0,0,5,9,9,7,4,4,0,0,0,0,0,0,5,3,2,9,7,1]

print("\nOriginal list:")
print(nums)
print("\nNumber of groups of non-zero numbers separated by zeros of the said list:")
print(test(nums)) 

Sample Output:

Original list:
[3, 4, 6, 2, 0, 0, 0, 0, 0, 0, 6, 7, 6, 9, 10, 0, 0, 0, 0, 0, 5, 9, 9, 7, 4, 4, 0, 0, 0, 0, 0, 0, 5, 3, 2, 9, 7, 1]

Number of groups of non-zero numbers separated by zeros of the said list:
4

Flowchart:

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:

Python Code Editor:

Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous: Sum a list of numbers. Write a Python program to sum the first number with the second and divide it by 2, then sum the second with the third and divide by 2, and so on.
Next: Write a Python program to compute the sum of non-zero groups (separated by zeros) of a given list of numbers.