Algorithms Problem Solving

Strong algorithm solutions come from a process: understand inputs/outputs, evaluate constraints, choose the best pattern/data structure, then build a clear step-by-step plan.

I/O
Understand
What enters and returns?
Constraints
Time / space limits
Pattern
Hash map, two-pointers...
Outline
Pseudocode then code
I/O -> Constraints -> Pattern -> Plan -> Code
A repeatable problem-solving framework

Algorithms Problem Solving

Learn a repeatable framework to solve algorithm questions faster and with fewer mistakes.
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1. Understand the Problem

Define input, output, and edge cases before writing code. Clarify what success looks like.
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2. Use Constraints to Guide Strategy

Large n often rules out O(n^2). Memory limits can rule out large auxiliary arrays.
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3. Pick the Right Pattern

Map problem signals to patterns: hash map, two-pointers, sliding window, DFS/BFS, dynamic programming.
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4. Outline Before Coding

Write concise pseudocode first, then implement and verify with sample tests.
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5. Framework Summary

I/O -> Constraints -> Pattern -> Plan -> Code. Reuse this flow in interviews and contests.
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Interactive Practice

Apply the framework on a classic problem and validate your approach choice.
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Framework to Code

Example implementation of the framework using a Two Sum helper.

solveTwoSum.ts
function solveTwoSum(nums: number[], target: number): number[] {
  // Pattern chosen from constraints: hash map for O(n)
  const seen = new Map<number, number>();

  for (let i = 0; i < nums.length; i++) {
    const needed = target - nums[i];
    if (seen.has(needed)) {
      return [seen.get(needed) as number, i];
    }
    seen.set(nums[i], i);
  }

  return [];
}
Problem-solving framework applied in code
AlgoAnimator: Interactive Data Structures