Python One-Liner: Find the Longest Common Prefix in a List of Strings! 🌟 #PythonTips #CodingShorts

🌟 Longest Common Prefix – Detailed Explanation vs. One-Liner

This script finds the longest common prefix among a list of strings, a common challenge in coding interviews and practical text processing. A common prefix is the initial segment that all strings in the list share. For example, given ["flower", "flow", "flight"], the longest common prefix is "fl".

Long Way Explanation:

Initial Check:

The function longest_common_prefix first checks if the input list is empty. If so, it returns an empty string.

Setting the Initial Prefix:

It initializes the variable prefix with the first string in the list. This serves as the initial guess for the longest common prefix.

Iterating Over the Strings:

The function then iterates over each of the remaining strings in the list. For each string, it checks if the current prefix is a prefix of that string using the .startswith() method.

Refining the Prefix:

If the current string does not start with the current prefix, the function shortens the prefix by removing its last character.

This process repeats until the current string does start with prefix, or until prefix becomes empty (which means there is no common prefix).

Returning the Result:

After processing all strings, the function returns the longest common prefix.

In the provided example, the function returns "fl".

One-Liner Explanation:

The one-liner imports os and immediately applies commonprefix() to the list ["flower", "flow", "flight"], then prints the result.

This built-in function provides a concise and efficient solution.

Both versions illustrate Python's flexibility—one showing a detailed, algorithmic approach, and the other showcasing the power of Python’s standard library for a clean, one-liner solution.

Codes:

📌 Long Way:

def longest_common_prefix(strs):
if not strs:
return ""
# Start with the first string as the prefix.
prefix = strs[0]
# Iterate over the remaining strings.
for s in strs[1:]:
# Shorten the prefix until it matches the beginning of s.
prefix = prefix[:-1]
if not prefix:
return ""
return prefix

# Example usage:
strings = ["flower", "flow", "flight"]
print(longest_common_prefix(strings))
# Output: "fl"

📌 One-Liner:

# Output: "fl"