desert forum
im doing this problem where you input the number of commands then input the commands and then the program runs it.
the answer was:
from collections import deque
d = deque()
for _ in range(int(input())):
method, *n = input().split()
getattr(d, method)(*n)
print(*d)
Im confused on how this for loop manages to run the commands inputted. Can anyone explain this ? Ex: you would input 1(3 of commands) and then append 1(commands) and then it would output the deque after the command: 1
magic pine
im doing this problem where you input the number of commands then input the comm...
getattr(d, method)(*n) is the equivalent of d.method(*n)
desert forum
`getattr(d, method)(*n)` is the equivalent of `d.method(*n)`
when i do d.method(*n)
it doesnt work tho
why is that
magic pine
Since method is a variable you can't do d.method. It won't evaluate your method variable it'll be trying to use a method d.method
When you do getattr(d, method) the method gets evaluated and replaced with the string from your user input
getattr(d, "user_input") like that
@desert forum
I guess more correctly d.method(*n) is the equivalent of getattr(d, "method")(*n)
desert forum
can you give an example of what would happen if *n = 1 and method = append ?
i just dont understand how it works in general
magic pine
getattr(d, "append")(1)
Which is equivalent to d.append(1)
getattr(d, "append") will return d.append
desert forum
and then it treats that as a line of code to be executed ?
magic pine
All lines of code are executed 🙂
magic pine
Yeah
You just need to use getattr vs dot notation because you are getting the method from user input
magic pine
Np
desert forum
should i close this or something ?
magic pine
You can, I'm not 100% sure how forums work tbh haha, I think it might close itself eventually?