C++编程计算1-1/2！+1/3！

以下是C++编程计算1-1/2！+1/3！的代码：

#include <iostream>
using namespace std;

int main() {
    int n;
    float sum = 1, f = 1;
    cout << "请输入一个整数n:";
    cin >> n;
    for (int i = 2; i <= n; i++) {
        f *= i;
        if (i % 2 == 0) {
            sum -= 1 / f;
        } else {
            sum += 1 / f;
        }
    }
    cout << "sum=" << sum << endl;
    return 0;
}