﻿ Python: Find the longest common prefix string amongst a given array of strings - w3resource

# Python: Find the longest common prefix string amongst a given array of strings

## Python Basic - 1: Exercise-70 with Solution

Write a Python program to find the longest common prefix string amongst a given array of strings. Return false If there is no common prefix.
For Example, longest common prefix of "abcdefgh" and "abcefgh" is "abc".

Sample Solution:

Python Code:

``````def longest_Common_Prefix(str1):

if not str1:
return ""

short_str = min(str1,key=len)

for i, char in enumerate(short_str):
for other in str1:
if other[i] != char:
return short_str[:i]

return short_str

print(longest_Common_Prefix(["abcdefgh","abcefgh"]))
print(longest_Common_Prefix(["w3r","w3resource"]))
print(longest_Common_Prefix(["Python","PHP", "Perl"]))
print(longest_Common_Prefix(["Python","PHP", "Java"]))
``````

Sample Output:

```abc
w3r
P
```

Pictorial Presentation:

Flowchart:

Python Code Editor:

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## Python: Tips of the Day

Iterating over dictionaries using 'for' loops:

I am a bit puzzled by the following code: d = {'x': 1, 'y': 2, 'z': 3} for key in d: print key, 'corresponds to', d[key] What I don't understand is the key portion. How does Python recognize ...

key is just a variable name.

```for key in d:
```

For Python 3.x:

```for key, value in d.items():
```

For Python 2.x:

```for key, value in d.iteritems():
```

To test for yourself, change the word key to poop.

In Python 3.x, iteritems() was replaced with simply items(), which returns a set-like view backed by the dict, like iteritems() but even better. This is also available in 2.7 as viewitems().

The operation items() will work for both 2 and 3, but in 2 it will return a list of the dictionary's (key, value) pairs, which will not reflect changes to the dict that happen after the items() call. If you want the 2.x behavior in 3.x, you can call list(d.items()).

Ref: https://bit.ly/37dm0Qo