def seq_diff(list_of_nums):
orig_list = list_of_nums
j = 0
while len(set(list_of_nums)) != 1:
lis = []
for i in range(len(list_of_nums)):
try:
lis.append(abs(list_of_nums[i]list_of_nums[i+1]))
except:
lis.append(abs(list_of_nums[i]list_of_nums[0]))
list_of_nums = lis
j = j+1
return orig_list, j
Sequence of Differences in Python
Carvia Tech  September 15, 2019  2 min read  26 views  Python Coding Problems
Given a set of four numbers representing a “circular array” we can test to see if the absolute values of the differences between each adjoining element will eventually coalesce into a single value.
For example, consider the set of four numbers: {1, 10, 8, 3}
.
We can repeatedly take the absolute values of the differences of the adjoining numbers. Since this is a circular array, calculate the value of the last element in the new array as the last number minus the first number.
For example, starting with {1, 10, 8, 3}

The first iteration will produce {9, 2, 5, 2} calculated as 1  10, 10  8, 8  3, 3  1.

The second iteration will produce {7, 3, 3, 7} calculated as 9  2, 2  5, 5  2, 2  9.

The third iteration will produce {4, 0, 4, 0} calculated as 7  3, 3 – 3, 3  7, 7 – 7.

The fourth iteration will produce {4, 4, 4, 4} calculated as 4  0, 0  4, 4  0, 0  4.
Input  Output 

1 0 0 0 
3 iterations were required for 1 0 0 0 
0 1 4 11 
5 iterations were required for 0 1 4 11 
0 0 0 2 
3 iterations were required for 0 0 0 2 
34 12 19 28 
4 iterations were required for 34 12 19 28 
100 200 321 345 
4 iterations were required for 100 200 321 345 
print(seq_diff([9934, 8543, 812, 1001]))
([9934, 8543, 812, 1001], 3)
Top articles in this category:
 Python coding challenges for interviews
 Python Flask Interview Questions
 Top 100 interview questions on Data Science & Machine Learning
 Google Data Scientist interview questions with answers
 Write a program for Hailstone Sequence in Python
 Find extra long factorials in python
 Python send GMAIL with attachment
Find more on this topic:
Machine Learning
Data science, machine learning, python, R, big data, spark, the Jupyter notebook, and much more
Last updated 1 week ago
Recommended books for interview preparation:
Similar Posts
 Configure Logging in gunicorn based application in docker container
 Connect to Cassandra with Python 3.x and get Pandas Dataframe
 Connect to MySQL with Python 3.x and get Pandas Dataframe
 Connect to Postgresql with Python 3.x and get Pandas Dataframe
 Python  Get Google Analytics Data
 Installing PySpark with Jupyter notebook on Ubuntu 18.04 LTS
 Python send GMAIL with attachment
 Send rich text multimedia email in Python
 Blueprints in Flask API Development
 Singleton Design Pattern in Python