Code RoomCoin change combinations
MediumPrep Room Coding #561

Coin change combinations

CodingAlgorithms & data structuresMid–Senior~22 min

Given coin denominations and a target amount, count the number of distinct multisets of coins (order does not matter) that sum to the amount; each denomination may be used any number of times. Return the count. 1 <= len(coins) <= 6, amount <= 60, denominations are distinct positive integers.

Implement
count_coin_combinations(coins: list[int], amount: int) → int
Examples
in[[1,2,5],5]out4
What a strong answer looks like

State your approach and its time/space complexity out loud before you optimize. Handle the edge cases (empty input, duplicates, overflow), and say why you chose this over the brute force. Green tests are the floor, not the grade.

0:00 of about 22 min
InputExpectedGot
[[1,2,5],5]4not run yetsample