If you remove the list to be looped, you will get terrible.

x = [1, 2, 3, 4, 5]
for i in x:
    x.remove(i)
    print(x)

>>>
[2, 3, 4, 5]  #Recognize
[2, 4, 5]  # ???If you pull out 1 and 2[3, 4, 5]Then!?!?
[2, 4]  # ???????

x = [1, 2, 3, 4, 5]
for i in x do
  x.delete(i)
  print(x)
end

>>>
[2, 3, 4, 5][2, 4, 5][2, 4] => [2, 4]

x = [1, 2, 3, 4, 5]
for i in x[:]:
    x.remove(i)
    print(x)

>>>
[2, 3, 4, 5]
[3, 4, 5]
[4, 5]
[5]
[]

from copy import copy

x = [1, 2, 3, 4, 5]
for i in copy(x):
    x.remove(i)
    print(x)

>>>
[2, 3, 4, 5]
[3, 4, 5]
[4, 5]
[5]
[]

Recommended Posts