LeetCode 322 Coin Change - Problem Statement

Given coin denominations and a target amount, find the minimum number of coins needed to make that amount. Return $-1$ if impossible.

With coins = [1,2,5] and amount = 11:

• $11 = 5 + 5 + 1$: $3$ coins.
• $11 = 5 + 2 + 2 + 2$: $4$ coins.
• Minimum: $3$.

With coins = [2] and amount = 3:

• Can't make $3$ with only $2$-coins.
• Return $-1$.

You can use each coin denomination unlimited times.

Constraints: $1 \le$ coins.length $\le 12$. $1 \le$ amount $\le 10^4$.