分析:

代码：

#include<iostream>
using namespace std;
int a[4] = {10, 20, 50, 100};
const int N= 1010;
int f[N];
int main()
{
    int n; cin>> n;
    f[0] = 1;
    for(int i = 0; i < 4; ++i)
    {
        for(int j = a[i]; j <= n; j++)
            f[j] += f[j - a[i]];
    }
    cout << f[n] <<endl;
    return 0;
}