1+1/1！+1/2！+…+1/20！求和c++

以下是使用C++计算1+1/1!+1/2!+...+1/20!的代码：

#include <iostream>
using namespace std;

int main() {
    double sum = 0.0, fact = 1.0;
    for (int i = 1; i <= 20; i++) {
        fact *= i;
        sum += 1.0 / fact;
    }
    sum += 1.0; // 加上1
    cout << "sum = " << sum << endl;
    return 0;
}

输出结果为：sum = 2.71828