Babylonian Method

#include <iostream>
using namespace std;

int main()
{
    double r, n, guess(2), prevGuess;
    cin >> n;
    for (int i = 0; i < 100; ++i)
    {
        r = n/guess;
        guess = (guess + r) / 2;
        if(prevGuess*1.01 > guess && prevGuess*0.99 < guess){
            break;
        }
        prevGuess = guess;
    }
    cout << guess;

    return 0;
}