Because you only have 2 eggs I don't think you can use a binary search algorithm (assuming I understood the question correctly). I think you'd have to start at floor 2, if that passed then jump to floor 4, etc. until you have an egg break (lets call this floor n). Then, you go to the floor below the one that broke the egg to see if an egg survives that drop. You'll then know, using only 2 eggs the highest floor you could drop from without breaking an egg (either n, n-1, or n-2).