Practice Arena

Python Coding Challenges

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467 challenges 330 easy 120 medium 17 hard
Bit Manipulation easy

Count Set Bits

Implement a function that returns the number of set bits (1s) in the binary representation of a non-negative integer.

bit-manipulation binary counting
+10 pts 15m
Bit Manipulation easy

Check Power of Two Bits

Implement is_power_of_two(n) that returns True if n is a power of two and False otherwise.

bitwise power-of-two integer
+8 pts 10m
Bit Manipulation easy

Rotate Bits Left

Implement a function that rotates the bits of an integer to the left by a specified number of positions.

bit-manipulation integer rotation
+10 pts 15m
Bit Manipulation medium

Bit Mask Permissions

Implement helper functions to compose bit masks and check permission bits using bitwise operators.

bitwise bitmasks permissions
+15 pts 20m
Bit Manipulation easy

Set kth Bit

Implement a function that sets the kth bit (0-indexed) of a non-negative integer to 1 and returns the result.

bit-manipulation bits integer
+10 pts 15m
Bit Manipulation easy

Compress Bits Run

Write a function that compresses a binary string by representing consecutive identical bits as a count-bit pair.

bit-manipulation strings compression
+10 pts 15m
Bit Manipulation easy

Sparse Number Check

Check if a non-negative integer is sparse, meaning its binary representation contains no adjacent 1 bits.

bitwise binary conditionals
+10 pts 15m
Bit Manipulation easy

Brian Kernighan count

Implement a function that counts set bits using Brian Kernighan's efficient algorithm.

bit-manipulation integers counting
+10 pts 15m

Showing 8 challenges

Guide: free Python coding challenges

Practice Python by solving problems

PythonSkillset challenges are hands-on coding exercises from beginner to advanced. Open a challenge, read the problem, write Python in the split-pane editor, and run tests with Pyodide — no install required.

How to use the arena

  1. Pick a category — basics, algorithms, strings, and more
  2. Open a challenge, read the statement, and edit the starter code
  3. Run tests, fix failures, then try a related quiz or tutorial lesson

Challenges vs tutorials and quizzes

Challenges test what you can build under constraints. For guided teaching, use our Python tutorials. For quick checks, try quizzes or copy snippets from code samples.