在计算机基础中，有个关于钱的经典问题：

给定一些面值的钱币，需要凑成一定金额的零钱，怎样凑才能使用到的钱币数最少?

#include <iostream>
#include <vector>
#define max_val 1e12;
using namespace std;



vector<double> money = {1,2,5,10,20,100};
double getMin(vector<double> money) {
    double min = max_val;
    for (auto& m: money){
        min = min(min, m);
    }
    return min;
}

int get_min_m(double m) {
    if (m < getMin(money)){
        return 0;
    }else (
        for (auto& cash: money) {
            if (cash == m) 
                return 1;
        }
    )
    int res_m = infinit;
    double c = 0;
    for (auto& cash: money) {
        int res_m = min(res_m, get_min_m(m - cash));
        c = cash;
    }
    if (c != 0) 
        cout << c;
    return res_m + 1;;
}

int dp(double  m) {
    double res_money = getMoneyRes(money);
    vector<double> est_money(ceil(m));
    int vel = 0;
    for(double i =0; i < m; i+=res_money) {
        if (i < getMin(money)) break;
        else if (abs(i - getMin(money)) < 1e-9) {
            vel = 1;
            break;
        }
        int min_val = 1e10;
        for(auto& m:  money) {
               min_val = min(min_val, est_money[i - m])
        }
        est_money[i] = min_val + 1;
    }
    return est_money[-1];
}

int main()
{
    double cash_total = 10.0;
    int res = get_min_m(m);
    int res = dp(m)
    
   cout << "Hello World";
   return 0;
}

ref: https://zhuanlan.zhihu.com/p/138159413
https://zhuanlan.zhihu.com/p/138328448