我将如何删除此 python 列表中 1 之前的所有零

Question

result = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0]

I want this list to be turned into

result = [1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0]

I have tried using a while loop to keep removing zeros until it finds a 1 but I cant seem to get that to work.

for x in result:
    while (x == 0):
        result.remove(0)

Answer 1

If there always is a 1, you could just find it and delete everything before it:

del result[:result.index(1)]

Or if it could be all zeros:

if any(result):
    del result[:result.index(1)]

or

try:
    del result[:result.index(1)]
except ValueError:
    pass

or

result.append(1)
del result[:result.index(1)]
result.pop()

Answer 2

One way using itertools.dropwhile :

from itertools import dropwhile

list(dropwhile(lambda x: x == 0, result))

Output:

[1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0]

Answer 3

Problem in your code is you are changing the list while iterating. Instead you can use while loop.

while result and result[0] == 0:
    result.pop(0)
print(result)

Output:

[1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0]

Answer 4

Or else try the following :

result = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0]
a=''
for i in result:
    a=a+str(i)
print(list(a.lstrip('0')))

Answer 5

result = [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 0, 0]

# prints index of 1st (leftmost) '1' encountered in the list
# print(result.index(1)) 

# print from that index to the wholw remaining list
print(result[result.index(1):])