Test case 1. Limak is in the kitchen for 7 minutes. He eats three cookies and after each of them he indeed drinks milk in the next minute. The answer is "YES".
Test case 2. Limak is in the kitchen for 5 minutes. In the first minute he eats a cookie and in the second minute he eats a cookie again, instead of drinking milk. The answer is "NO".
Test case 3. Here Limak doesn't eat any cookies. The answer is "YES" because the condition is satisfied (there is no situation when Limak eats a cookie but doesn't drink milk in the next minute).
Test case 4. Limak eats a cookie and doesn't drink milk in the next minute so the answer is "NO".