Given a list of coin denominations and a target amount, find the minimum number of coins needed to make up that exact amount. Each coin denomination can be used an unlimited number of times. Return -1 if it is not possible to make up the amount using the given coins. Return 0 if amount is 0. Return -1 for null or invalid inputs.
Examples:
Input: coins = [1, 5, 10, 25], amount = 36
Output: 3
Explanation: Use 25 + 10 + 1 = 36, which requires 3 coins
Input: coins = [1, 5, 10], amount = 15
Output: 2
Explanation: Use 10 + 5 = 15, which requires 2 coins
Input: coins = [2], amount = 3
Output: -1
Explanation: Cannot make 3 using only coins of denomination 2
Input: coins = [1, 2, 5], amount = 0
Output: 0
Explanation: Zero amount requires zero coins
Input: coins = null, amount = 10
Output: -1
Apex Code Editor
Welcome to Lightning Challenge!
Create an Account
Sign up to track your progress, earn points, and compete with others. Your solutions will be saved automatically.
Create accountHow It Works
- • Write your solution in the code editor
- • Connect your Salesforce org to test
- • Submit to check if your solution passes
- • Use hints if you get stuck
Contest Alert
🏆 #CodeEveryDay May 2026
Contest runs May 1 - 31. Complete challenges to climb the leaderboard!
Only the 31 daily challenges shown during this contest count toward points. Earlier dailies don't carry over.