#include<iostream> #include<vector> using namespace std; class Solution{ public: int change(int amount,vector<int> &coins){ int len=coins.size(); vector<int> dp(amount+1,0); dp[0]=1; for(int i=1;i<=len;++i) for(int j=0;j<=amount;++j) if(j-coins[i-1]>=0) dp[j]+=dp[j-coins[i-1]]; return dp[amount]; } };