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Whether you're grinding LeetCode for interviews or pushing your Codeforces rating, AlgoPath gives you progressive hints and AI feedback that teach — without giving away the answer.
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Interview prep and contest training, in one place
Guided hints that teach, not spoil
Progressive hints unlock as you think through the problem. Each one nudges your thinking forward without giving away the solution.
Given coins of denominations coins and a target amount, return the fewest number of coins needed to make up that amount. Return -1 if the amount cannot be made.
Think about building the answer from smaller subproblems. If you already knew the minimum coins for every amount less than your target, how would that help you answer the original question?
Define dp[i] as the minimum coins needed for amount i. For each amount, try subtracting every coin — you're left with a subproblem you've already solved. Take the best option.
Reveal after you've spent time on hint 2
Instant feedback on your code
After you've worked through hints, get AI-powered analysis of your solution. Learn what works, what doesn't, and how to improve.
def coinChange(coins, amount):
dp = [float('inf')] * (amount + 1)
dp[0] = 0
for i in range(1, amount + 1):
for coin in coins:
if coin <= i:
dp[i] = min(dp[i], dp[i - coin] + 1)
return dp[amount] if dp[amount] != float('inf') else -1O(n × m) time, O(n) space — n is amount, m is coins. Standard bottom-up DP, optimal for this approach.
Clean DP formulation, handles the impossible case correctly, follows the standard bottom-up pattern.
Inner loop could break early once dp[i] = 1. Minor optimization — solution is correct and idiomatic.
Everything built for learning
Practice smarter, improve faster.
Guided Hints
Three progressive hints per problem. Works for interview prep and competitive programming — nudges your thinking without spoiling the solution.
AI Code Review
Instant feedback on complexity, correctness, and approach. Learn what works and what to improve.
Curated Problems
LeetCode patterns for FAANG interviews. Codeforces rounds for contest prep. Recommended based on your skill level and focus.
Track Progress
Watch your rating climb whether you're targeting a FAANG offer or a higher contest rank. Stats on every solve, hint used, and streak maintained.
Gamified progression
Earn XP. Climb the ranks.
Every problem you solve earns XP. Harder problems and fewer hints mean bigger rewards.
Newcomer
Lv. 1
Apprentice
Lv. 2–4
Solver
Lv. 5–8
Coder
Lv. 9–12
Expert
Lv. 13–17
Master
Lv. 18–22
Grandmaster
Lv. 23–27
Legendary
Lv. 28+
XP required grows with each tier — consistent practice is the only path forward.
Pricing
Built by a competitive programmer.
Priced like one, too.
The free plan isn't a trial — it's fully usable. We know how it feels to be gated out of tools you actually need.
Free
$0
Forever. No credit card.
- Unlimited problem practice
- 3 hint sessions per day
- All 3 hints visible per session
- XP, levels & streaks
- Notes (3/day)
- 14-day activity history
Pro
$8
/ moor $65/yr — save 32%
- Everything in Free
- Unlimited hint sessions
- Unlimited notes + full history
- Model selection for hints
- Unlimited AI code review
- Streak freeze (1/month)
Elite
$16
/ moor $130/yr — save 32%
- Everything in Pro
- Adaptive difficulty hints
- Hint style: Socratic / Minimal
- Insights dashboard
- Priority generation
Payments coming soon. Full plan comparison →
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in 30 seconds.
No setup. No paywalls. Interview prep or competitive programming — pick a problem, get a hint, and actually learn.
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