恭喜你找到彩蛋！

#include<bits/stdc++.h>

using namespace std;

double calculatePi(int n){

    double pi = 0.0;

    for(int i=0;i<n;i++){

        pi+=4.0 * (1-(i%2)*2) / (2*i+1);

    }

    return pi;

int main(){

    int n;

    cout<<"迭代次数："

    cin>>n;

    double approxPi = calculatePi(n);

    cout<< "使用" << n << "次迭代得到的π近似值为：" << approxPi << endl;

转载至  https://blog.csdn.net/lei967809/article/details/138395509