Coin Change I: The Fewest Tokens for an Amount, Impossible Amounts & Why Greedy Fails
This lesson is part of the course
In this lesson
You check a half-filled fewest-tokens table with three “via” columns built from XLOOKUP, extend it to amounts 13–15 with MIN, and show that the greedy rule pays amount 10 with more tokens than the table.
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Lessons in this course
- Overlapping Subproblems: Counting the Calls of a Naive Recursion Locked
- Bottom-Up Tables: Ways to Climb n Stairs with 1-, 2- or 3-Steps Locked
- Coin Change I: The Fewest Tokens for an Amount, Impossible Amounts & Why Greedy Fails Locked
- Coin Change II: Counting the Ways Token by Token – and Why Loop Order Matters Locked
- 0/1 Knapsack: The Capacity × Item Grid, MAX(Skip, Take) and the Traceback Locked
- Longest Common Subsequence: Letters with MID, the LCS Grid and the Traceback Locked
- Grid Paths & Cheapest Paths: Blocked Squares, Cost Grids and the Way Back Locked
- Capstone: Longest Increasing Subsequence and Brute Force vs Dynamic Programming Locked