Amicable Numbers Check
Write a function that checks if two numbers are an amicable pair by comparing sums of proper divisors.
Armstrong Number Check
Implement a function that checks if a given integer is an Armstrong number.
Multiply without multiply
Write a function that multiplies two integers using only addition, subtraction, and bit shifts — no * operator.
Modular Inverse
Implement a function that returns the modular inverse of a modulo m, or -1 if it does not exist.
Chinese Remainder Theorem
Solve a system of congruences with pairwise coprime moduli using the Chinese Remainder Theorem.
Showing 1–5 of 5 challenges · easy · Math & Number Theory
Math & Number Theory — Python coding challenges
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This page lists math & number theory challenges — real Python problems you solve in the browser IDE with instant test feedback. Each challenge includes a clear brief, starter code, and automated checks.
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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.