Help me to fix the problem

Question

Write a function to find the longest common prefix string amongst an array of strings.

If there is no common prefix, return an empty string
My code is:
a = ["flower","flight"]
if len(a) == 0:
print(" ")
result = " "
lens = [len(str) for str in a]
mim = min(lens)
for i in range(1,mim+1):
pre = a[0][:i]
for q in a:
if q[:i] == pre:
result = result+pre
print(result)

Answer 1

Some little logical bugs....still not valid for more than 2 strings

a = ["flower","flight"]
if len(a) == 0:
print(" ")
result = " "
lens = [len(str) for str in a]
mim = min(lens)
for i in range(1,mim+1):
pre = a[0][:i]
for q in a[1:]:
if q[:i] == pre:
result = pre
print(result)

Answer 2

✩✮★✮✩ yes....and some more problems.
But my idea was step by step.
Shahir has problems with logic. Better we don't improve all in one

Answer 3

Why did you use the a[1:] why not the all the elements in the list??

Answer 4

pre=a[0][:i]
First element is used