using System;

namespace PremiereCalculatrice
{
	class MainClass
	{
		public static void Main (string[] args)
		{
			Console.Write ("valeur = ");
			double a = double.Parse(Console.ReadLine());
			Console.Write ("operateur = ");
			char op = char.Parse(Console.ReadLine());
			Console.Write ("valeur = ");
			double b = double.Parse(Console.ReadLine());
			double resultat = 0;
			bool erreur = false;
			switch(op)
			{
			case '+' : resultat = a + b; break;
			case '-' : resultat = a - b; break;
			case '*' : resultat = a * b; break;
			case '/' : resultat = a / b; break;
			default : erreur = true; break;
			}
			if (erreur)
				Console.WriteLine ("Opérateur " + op + " inconnu.");
			else 
				Console.WriteLine (a + " " + op + " " + b + " = " + resultat + ".");
		}		
	}
}