Coin Change
You are given an integer array coins representing different denominations of coins and an integer amount representing a total amount of money.
Return the fewest number of coins needed to make up the given amount.
You may use each coin denomination unlimited times.
If the amount cannot be made up using the given coins, return -1.
Example 1
Input
n = 3 coins = [1, 2, 5] amount = 11
Output
3
Explanation
The minimum number of coins is:
5 + 5 + 1 = 11
So the answer is 3.
Example 2
Input
n = 1 coins = [2] amount = 3
Output
-1
Explanation
It is impossible to make amount 3 using only coins of denomination 2.
Constraints
Hints:
Hint 1
Let dp[i] represent the minimum number of coins needed to make amount i.
Hint 2
For every coin, if the current amount is at least the coin value:
dp[i] = min(dp[i], dp[i - coin] + 1)
Author & Technical Reviewer
Technically reviewed by: ExamAdda Technical Review Team
Technical Reviewers, ExamAdda
Software engineers at ExamAdda who check every article's definitions, complexity claims and code examples before and after publishing.
Published
Aug 23, 2026
Last updated
Aug 23, 2026
Content Verification Methodology
Definitions and complexity claims were checked against authoritative computer-science references. Code examples were compiled and tested with standard, boundary and edge-case inputs.
Expected Output