Question

编写程序计算级数ex=1+x+x2/2!+x3/3!+...+xn/n!的值.

要求：要采用函数调用，一个函数实现n！，另一个函数实现xn

Answer 1

#include<iostream>

using namespace std;

int pow(int x, int n);
int f1(int n);

int main(int argc, char* argv[])
{
int x, n;
double ex = 1;

cin >> x;
cin >> n;
for (int i=1; i<=n; i++)
ex += pow(x, i) / (f1(i) * 1.0);

cout << ex << endl;

system("pause");
return 0;
}
int f1(int n)
{
int s = 1;
for (int i=2; i<=n; i++)
s *= i;
return s;
}
int pow(int x, int n)
{
int s = 1;
for (int i=1; i<=n; i++)
s *= x;
return s;
}