Dictionary in C#

Key Values

Maths 70
Phy 80
Chm 65

Path:

System.Collections.Generic.Dictionary;

Program:

using System;
using System.Collections.Generic;
namespace Dictionary {
    class Program {
        static void Main(string[] args) {
            Dictionary < string, int > Marks = new Dictionary < string, int > ();
            Marks.Add("Maths", 70);
            Marks.Add("Phy", 79);
            Marks.Add("Chem", 90);
            int m = Marks["Chem"];
            Console.WriteLine(m);
            Console.ReadKey();
        }
    }
}