Decreasing Number staircase in python 2.7

Question

I am fairly new to array data structures. I am trying to print the below pattern in python.

Here is my code:

a = [1,2,3,4,5]
n = len(a)
for i in range(n, 0, -1):
    for j in range(i):
        print a[j],

Output: I am getting the correct order. I just can't seem to arrange the answer in the desired format. Any suggestions?

1 2 3 4 5 1 2 3 4 1 2 3 1 2 1

While not a duplicate question, this may be useful to read https://stackoverflow.com/questions/493386/how-to-print-without-newline-or-space — Cameron Aavik, Oct 16 '17 at 04:28
@falsetru Tried that. can't seem to get it to work. can you please provide a more elaborate explanation? — suyash gautam, Oct 16 '17 at 04:36

score 1 · Accepted Answer · answered Oct 16 '17 at 06:12

If you're really just interested in learning about list manipulations, and don't need exactly the output you've shown, you might consider this approach, which makes use of basic list indexing:

for i in range(n, 0, -1):
    print(a[:i])

Output:

[1, 2, 3, 4, 5]
[1, 2, 3, 4]
[1, 2, 3]
[1, 2]
[1]

Along those lines, you can get your specified output by converting the values in each row to type str, joining each row's characters, and then printing:

for i in range(n, 0, -1):
    print(''.join(str(el) for el in a[:i]))

Output:

Decreasing Number staircase in python 2.7

1 Answers1