derivative.cpp

#include <iostream>
#define MAX 100
using namespace std;

int main(void)
{
    int i, j, m, n;
    double a[MAX];

    cout << "please input n: ";
    cin >> n;

    cout << "please input a[n], a[n-1]...,a[1],a[0](one space between them):" << endl;
    for (i = n; i >= 0; --i)
    {
        cin >> a[i];
    }

    cout << "please input m(m <= n):";
    cin >> m;

    for (i = n; i > m - 1; --i)
    {
        for (j = i; j > i - m; --j)
        {
            a[i] *= j;
        }
    }

    cout << "The answer:" << endl;
    for (i = n; i > m; --i)
    {
        cout << a[i] << 'x' << '^' << i - m << '+';
    }
    cout << a[m] << endl;

    return 0;
}