using System;

public class Program

{

    public static void Main()

    {

         Console.WriteLine("BMI Calculator");

            Console.WriteLine("===========");

            Console.WriteLine();

​

            Console.Write("Weight in kg: ");

            int kg;

            kg = Convert.ToInt32(Console.ReadLine());

​

            Console.Write("\n Height in m: ");

            int m;

            m = Convert.ToInt32(Console.ReadLine());

​

            Console.Write("\n age:");

            int age;

            age = Convert.ToInt32(Console.ReadLine());

        if ( age < 20)

        {

        Console.WriteLine("NOT VALID");

        }

        else {

​

            int BMI;

            BMI = kg / ( m * m ) ;

​

            if (BMI < 18.5)

            { Console.WriteLine("UNDERWEIGHT"); }

            if (BMI >= 19 & BMI <= 24.9) 

            { Console.WriteLine("\n NORMAL WEIGHT"); }

            if (BMI > 25 & BMI < 29.9 )

            { Console.WriteLine("\n OVERWEIGHT"); }

            if (BMI > 30 )

            { Console.WriteLine("\n OBESSE"); }

            Console.ReadLine();

        }

    }

}