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While statement explanation - alkhufu2 - Aug-31-2020
I am new to Python. I get while and for loops pretty well so far but I DO NOT understand the output of this code. Please explain this. I would most appreciate it.
n = 3
while n > 0:
print(n + 1, end=' ')
n -= 1
else:
print(n)Output:4 3 2 0
Thank you for any help!
RE: While statement explanation - nilamo - Aug-31-2020
Let's walk through the code, line by line, and keep track of what
n is.n = 3 # 3
while n > 0: # 3
print(n + 1, end=' ') # 3 (print 4)
n -= 1 # 2
while n > 0: # 2
print(n + 1, end=' ') # 2 (print 3)
n -= 1 # 1
while n > 0: # 1
print(n + 1, end=' ') # 1 (print 2)
n -= 1 # 0
else:
print(n) # 0
RE: While statement explanation - deanhystad - Sep-01-2020
What is it you don't understand? That the numbers printed count down from 4 instead of 3, or that they all appear on the same line?
The numbers start at 4 and count down to 1 because you are printing n+1, not n. The value for n starts at 3 and it ends at 0, so the output starts at 3+1 and ends at 0+1. nilamo covers this very well.
The numbers are all printed on the same line because you replaced the "end" string. Normally the print command end = '\n' which is a new line, but you replaced this with a space. So when you print it just prints the value of n+1 and a space instead of the value of n+1 and a newline character.
RE: While statement explanation - alkhufu2 - Sep-02-2020
Thank you all for the response. It was the output itself (the integers). Nilamo described it perfectly. I see where the breakdown in understanding the way it executed past the first iteration.