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
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