New to programming need help with C# Birthday Party Problem - I am not at all sure how to right this? Could I get some help plea

Question

under "// your code goes here:"

I am not at all sure how to right this? Could I get some help please?

Birthday Party Problem:

You are organizing a birthday party and need N number of balloons. You already have 14 balloons for decoration.
The given program takes the N required number of balloons as input.

Task
Calculate and output how many balloons you need to buy.

Sample Input
30

Sample Output
16

Explanation
The count of the balloons you need to buy is calculated by this formula: balloons-14. So, in this case, the count is 30-14=16.

Code:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace SoloLearn
{
class Program
{
static void Main(string[] args)
{
int balloons = Convert.ToInt32(Console.ReadLine());
//your code goes here

}
}
}

Answer 1

You already have 14 balloons in your hands. You just have to calculate how many balloons you need to add to complete the decoration.
16 is to 30, 6 is to 20 and so on