Count Word Occurrences in a List
PYTHON coding challenge · Difficulty: easy · Topic: Data Structures · +50 XP
Problem
Given the list words, build a dict counts mapping each word to how many times it appears, then print counts['spark'].
Example Input
The data below is already defined — do not redefine it.
`python
words = ['spark', 'python', 'spark', 'sql', 'spark', 'python']
`
Expected Output
`
3
`
Explanation
Each word is counted every time it appears, so a word occurring twice maps to 2. Words are matched exactly as given — no case folding and no punctuation stripping.
Notes
- Print the result — the grader reads standard output
- Do not redefine the input; it is provided for you
What this PYTHON challenge teaches you
“Count Word Occurrences in a List” is a easy-level PYTHON challenge focused on Data Structures. Working through it gives you hands-on practice with beginner — the kind of transformation you are asked to write in real data engineering work and in technical interviews. You can solve it directly in the browser: the dataset is pre-loaded, so you write the query or DataFrame code, run it, and compare your output against the expected result immediately.
Concepts covered
- beginner
How to approach it
If you get stuck, work through these steps in order before looking at a full solution — each one narrows the problem down:
- A dict maps each word to how many times you have seen it.
- dict.get(w, 0) returns 0 for a word you have not seen yet, so counts[w] = counts.get(w, 0) + 1 works on the first sighting too.
How to practise it on PySpark.in
Open the challenge, write your Python code in the editor and press Run to execute it against the sample dataset. Submitting checks your output against every test case, including hidden ones, so you find out straight away whether your logic holds up. You can retry as often as you like, and each solved challenge adds to your XP.
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Frequently asked questions
Do I need to install Spark or a database to solve this?
No. The PYTHON environment runs in your browser with the sample data already loaded, so there is nothing to install or configure.
Is this challenge free?
Yes - the problem, the sample dataset, the hints and unlimited test runs are free.
What level is it?
It is rated easy and covers Data Structures.