initialize i and j in for loop

Question

Hello,

I am trying to calculate a binomial:

 int X;
    int Y;
    int n = Convert.ToInt32(Console.ReadLine());   // number of horses    6
    int p = Convert.ToInt32(Console.ReadLine());   // number of try           2
    int i = 1;
    int k = 1;

    Console.WriteLine(" Entrez le nombre de cheveux partants:");
    Console.WriteLine(" Entrez le nombre de cheveux joués:");

      for (i, k; i < n && k < p; n++, k++  )

     {
      X *= i  / (i - k); 
      Y *= i  / (k  * (i – k) );

     }

      Console.WriteLine(" Dans l’ordre, une chance sur :{0}", X);
      Console.WriteLine(" Dans le désordre, une chance sur :{0}", Y);

I get an error: only assigment in my for loop.
Is there a way i can use two variables in the same loop?

Thank you

Answer 1

The logic for factorial is fairly basic. Below is a lambda but the logic could also be a utility function.

Func<int, int> factorial = (n) =>
{
    int res = 1;
    while (n != 1)
    {
        res = res * n;
        n = n - 1;
    }
    return res;
};

int results = factorial(5);
Console.WriteLine(results);

I am trying to calculate a binomial

Are you trying to graph a binomial? Or solve for X and Y where they cross an axis?

Answer 2

The C# for...loop reference documentation explains and illustrates the for...loop usage.

The following code runs but the logic does not make sense.

int X = 0;  
int Y = 0;  
int n = Convert.ToInt32(Console.ReadLine());   // number of horses    6  
int p = Convert.ToInt32(Console.ReadLine());   // number of try           2  
int i = 1;  
int k = 1;  
  
Console.WriteLine(" Entrez le nombre de cheveux partants:");  
Console.WriteLine(" Entrez le nombre de cheveux joués:");  
  
for (i = 0, k = 0; i < n && k < p; n++, k++)  
{  
    X *= i / (i - k);  
    Y *= i / (k * (i - k));  
}  
  
Console.WriteLine(" Dans l’ordre, une chance sur :{0}", X);  
Console.WriteLine(" Dans le désordre, une chance sur :{0}", Y);