```
class Solution {
public:
int coinChange(vector<int>& coins, int amount) {
vector<int> dp(amount + 1, INT_MAX);
dp[0] = 0;
for (int i = 0; i <= amount; i++) if (dp[i] != INT_MAX) {
for (auto j : coins) if (i + j <= amount) dp[i + j] = min(dp[i + j], dp[i] + 1);
}
return dp[amount] == INT_MAX ? -1 : dp[amount];
}
};
```