static double Exponentiate(double n1, int power) 
{
    double number = n1; // assign a seperate variable to be equal to n1 so n1 can stay the exponent base
    for (int i = (power - 1); i > 0; i--) // assign i to equal power - 1, and while i > 0, subtract one from i 
        number *= n1; // 'number' is equal to number * n1
    return number; // return the result
}

// Example implementation:
Console.WriteLine(Exponentiate(100, 3));
// Output: 1000000
