Climbing Stairs
Count the number of distinct ways to reach the top of n stairs
Coin Change (Minimum Coins)
Find the minimum number of coins needed to make a given amount
Coin Change II LC 518: DP Count Ways (Unbounded)
Medium DP/unbounded knapsack: dp[x]+=dp[x-c] counts coin change ways (no permutations). O(n·amount) time, O(amount) space. Practice now.
Fibonacci Numbers
Calculate the nth Fibonacci number using dynamic programming
Word Break
Determine if a string can be segmented into space-separated words from a dictionary.
Word Break II (LC 140) — DFS + Memo DP (Hard)
Solve LeetCode 140 Word Break II with DFS + memoization DP. Output-sensitive (≈O(n²)+answers). Step-by-step for interviews—practice now.