print(*range(1, int(input())+1), sep='')
This was the code I found in a discussion on hacker rank. But I did not understand it. Can anyone please explain this?
Add a comment
|
2 Answers
So, from what I can tell, this is how it works:
int(input())
This takes input from the user. Next;
range(1,...+1)
This creates a range from 1 to our number we inputted earlier. The +1 means that it will include the max number. And then:
print(*...,sep='')
The * sign, from what I can tell, just effectively returns each value in our range one to be printed.
The sep='' just means each value is separated by '' or nothing.
Hope this is useful to you.
[EDIT]
More on star and double star expressions in this post: What does the star and doublestar operator mean in a function call?
2 Comments
mozway
The
* performs unpacking, each element will be a parameter of print
Agent Biscutt
@mozway thanks, I didn't know that before.
Ok so we have print function. Inside we have this strange *range(1, int(input())+1) this is range function which return value from 1 to n (n is typed in input) in a form of a range object. * unpack this object to form like: 1 2 3 4 ... with spaces, so we have this sep='', keyword argument that makes separation from space to '' (no separate between).
Also you can do it like that:
n = input("Type integer value: ")
try:
[print(x+1,end="") for x in range(int(n))]
except ValueError:
exit("Typed string not number")
1 Comment
Matthias
(Mis)using a list comprehension just to invoke a side effect isn't the best of ideas. It confuses future readers.