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🎯 Learn the Basics

Foundation: Math, Logic Building, Problem Solving

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Master the Fundamentals

These basics are the foundation of all DSA. Don't skip them! Use hints to develop your problem-solving intuition.

Problems (6)

Reverse a Number

Easy

Given an integer, reverse its digits. Handle negative numbers and overflow.

StriverLeetCode
Pattern: Math / Modulo

Palindrome Number

Easy

Determine if an integer is a palindrome (reads same forwards and backwards).

StriverLeetCode
Pattern: Math / Two Pointers

Armstrong Number

Easy

Check if a number equals sum of its digits raised to the power of number of digits.

Striver
Pattern: Math

Count Digits

Easy

Count number of digits in a given integer.

Striver
Pattern: Math / Logarithm

GCD and LCM

Easy

Find Greatest Common Divisor (GCD) and Least Common Multiple (LCM) of two numbers.

StriverLeetCode
Pattern: Euclidean Algorithm

Check Prime Number

Easy

Determine if a number is prime. Optimize to check only up to sqrt(n).

StriverLeetCode
Pattern: Math / Optimization
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Select a Problem

Choose a problem from the list to start practicing