Coding Problem
💬 Problem: The way to Discover the Longest Line or String From a File in Python?
Given the next textual content file:
Relying on what precisely you’re on the lookout for, you wish to discover the longest string phrase (A) or the longest line (B) within the file.
with out python we would all need to write java code
Let’s dive into each variants subsequent.
Technique 1: Discover Longest Line in Textual content File utilizing Python
To search out the longest line in a textual content file utilizing Python, open the file utilizing the open() operate and skim the file content material in a record of traces utilizing file.readlines() operate. Then name the max(traces, key=len) operate on the record of traces utilizing the size operate as a key to search out the longest line.
Right here’s the code:
with open('my_file.txt', mode="r") as f:
traces = f.readlines()
longest_line = max(traces, key=len)
print('The longest line is:', longest_line)
The output is:
The longest line is: we would all need to
You might wish to take a look at the next tutorials that can assist you perceive the fundamentals of the options used on this snippet:
Or why not open all 4 tutorials and skim them in 1 minute per tutorial? 4 minutes properly spent! 🦄
Word you’ll be able to one-linerize this utilizing the next code snippet:
print(max(open('my_file.txt').readlines(), key=len))
# we would all need to
Technique 2: Discover Longest String Phrase in a Textual content File utilizing Python
A easy and easy option to discover the longest string phrase in a textual content file is to open the file, loop over all traces utilizing file.readlines(), break up every line into a listing of phrases utilizing string.break up(), loop over this record of phrases, and maintain monitor of the longest phrase in a variable.
Right here’s the Python snippet that finds the longest phrase in a textual content file:
with open('my_file.txt', 'r') as f:
longest_word = ''
for line in f.readlines():
for phrase in line.break up():
if len(phrase)>len(longest_word):
longest_word = phrase
print('The longest phrase within the file is:', longest_word)
Right here’s the right output, i.e., the longest phrase within the textual content:
The longest phrase within the file is: with out
Word, you can too one-linerize this utilizing the next method of mixing record comprehension and the max() operate:
longest = max([word for line in open('my_file.txt').readlines() for word in line.split()], key=len)
The end result is identical:
print('The longest phrase within the file is:', longest)
# The longest phrase within the file is: with out
In case you’re confused by the one-liner answer, no worries. First take a look on the record comprehension tutorial.
👉 Really helpful Tutorial: A Easy Information to Python’s Record Comprehension
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