C# Coding Challenge: What will this code do?

time to read 2 min | 218 words

What is the output of this code?

 IDictionary<object,string> instanceToKey = new Dictionary<object, string>();

 IDictionary<string, int> keyToCost = new Dictionary<string, int>();

 var inst1 = new object();
 var inst2 = new object();

 instanceToKey[inst1] = "one";
 keyToCost["one"] = 1;

 instanceToKey[inst2] = "two";
 keyToCost["two"] = 2;

 string value = null;
 foreach (var key
     in (from inst in new[]{inst1, inst2, new object()}
         where instanceToKey.TryGetValue(inst, out value) 
         select value))
     int cost;
     if(keyToCost.TryGetValue(key, out cost))
         Console.WriteLine("Key: {0}, Cost: {1}", key, cost);