Задача на вклады: простые и сложные проценты

#include <iostream>
using namespace std;
int main()
{
    const int start = 100;
    const float first = 0.1;
    const float second = 0.05;
 
    int n = 2;
 
    double sum1 = start;
    double sum2 = start;
        sum1 = sum1 + first*start*n;
        sum2 = start*pow(1+second,n);
 
 
        while (sum1>sum2)
    { 
        n=n+1;
        sum1 = sum1 + first*start*n;
        sum2 = start*pow(1+second,n);
    }
 
 
    cout << "the number of the years is  " << n << "\n";
    cout << "the first sum is  " << sum1 << "\n";
    cout << "the second sum is  " << sum2 << "\n";
 
    system("pause");
    return 0;
}

#include <iostream>
using namespace std;
int main()
{
    setlocale(LC_ALL, "rus");
    float dafna=100, cleo=100;
    int year = 0;
    do
    {
        dafna += 10;
        cleo = cleo / 20 + cleo;
        year++;
    } while (cleo < dafna);
    cout << "Потребуется " << year << " лет" << endl;
    cout << "Сумма Дафны:" << dafna << endl;
    cout << "Сумма Клео: " << cleo << endl;
    system("pause");
    return 0;
}

#include <iostream>
using namespace std;
int main()
{
    const int start = 100;
    const float first = 0.1;
    const float second = 0.05;
 
    int n = 0;
 
    double sum1 = start;
    double sum2 = start;
 
 
    while (sum1>=sum2)
    {
        n = n + 1;
        sum1 = sum1 + first*start;
        sum2 = sum2*second+sum2;
    }
 
    cout << "the number of the years is  " << n << "\n";
    cout << "the first sum is  " << sum1 << "\n";
    cout << "the second sum is  " << sum2 << "\n";
 
    system("pause");
    return 0;
}

        sum1 = sum1 + first*start;
        sum2 = sum2*second+sum2;