经历一番波折终于写出来了, 在博客园记录一下~~

        给你若干钱, 有1元, 5元, 10元, 25元, 50元这5种小钱可以换. 求共有多少种方法.

#include 
    
     using namespace std;int s(int a){     switch (a)     {     case 1: return 1; break;     case 2: return 5; break;     case 3: return 10; break;    case 4: return 25; break;    case 5: return 50; break;    }}int way(int j, int k = 5){    int s(int a);    if (j == 0)        return 1;    else if ((j < 0)||(k == 0))        return 0;    else        return way(j, k - 1) + way(j - s(k), k);}int main(){    int p;    int way(int j, int k =5);    cout << "请输入钱数:";    cin >> p;    cout << way(p, 5);}
    

        要是想一一列出1元, 5元, 10元, 25元, 50元各换了多少张, 再写一个程序.

#include 
    
     using namespace std;//1,5,10,25,50int main(){    int a, i, j, k, o, p,q = 0;    cin >> a;    for (i = 0; i <= (int)a/50; i++)    {for(j = 0; j <= (int)(a - 50*i)/25; j++)    {for(k = 0; k <= (int)(a-50*i-j*25)/10; k++)    {for(o = 0; o <= (int)(a-50*i-j*25-k*10)/5; o++)    {for(p = 0; p <= (int)(a-50*i-j*25-k*10-o*5); p++)    {     if(50*i+25*j+10*k+5*o+p == a)     {          q++;      cout <<"50的换"<
     <<"张,25的换"<
      
       <<"张,10的换"<
       
        <<"张,5的换"<
        
         <<"张,1块的换"<
         
<<"张."<