Puzzle: You have to make N (≥ 1) pancakes using a skillet that can hold only two pancakes at a time. Each pancake has to be fried on both sides. Frying one side of a pancake takes one minute, regardless of whether one or two pancakes are fried at the same time. What is the minimum amount of time required to fry the pancakes?
Solution: Let’s try to solve this problem case-wise:
- If N = 1: This is a trivial case, where time to fry the pancakes is 2 minutes, as both sides need to be fried.
- If N is even: The time, in this case, is N minutes. Since two cakes can be fried at one time, N/2 minutes are needed to fry the cakes on one side. Hence, the total time taken to fry the cakes on both sides is N minutes.
If N is odd: This case is a bit tricky. Let’s consider when the value of N = 3. We can fry 3 cakes in 3 minutes, as follows.
- Firstly, fry pancakes 1 and 2 on one side.
- Then fry pancake 1 on the second side together with pancake 3 on the first side.
- Finally, fry the pancakes 2 and 3 on the second side together.
- If N is odd and greater than 3: We can first fry the 3 pancakes in 3 minutes and then the remaining (N – 3) pancakes, which is even, in (N – 3) minutes.
- Puzzle 31 | (Minimum cut Puzzle)
- Minimum number of moves required to solve a Jigsaw Assembly Puzzle
- Puzzle | Minimum colors required to color a chessboard with no two given pair threatening each other
- Puzzle 15 | (Camel and Banana Puzzle)
- Puzzle 24 | (10 Coins Puzzle)
- Puzzle 27 | (Hourglasses Puzzle)
- Puzzle 28 | (Newspaper Puzzle)
- Puzzle 29 | (Car Wheel Puzzle)
- Puzzle 33 | ( Rs 500 Note Puzzle )
- Puzzle 34 | (Prisoner and Policeman Puzzle)
- Puzzle 36 | (Matchstick Puzzle)
- Puzzle 38 | (Tic Tac Toe Puzzle)
- Puzzle 39 | (100 coins puzzle)
- Puzzle 51| Cheryl’s Birthday Puzzle and Solution
- Puzzle 81 | 100 people in a circle with gun puzzle
- Puzzle 85 | Chain Link Puzzle
- Puzzle | Elevator Puzzle
- Puzzle | 3 Priests and 3 devils Puzzle
- Puzzle | Man fell in well Puzzle
- Puzzle | ( Distance, Time and Work)
If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to firstname.lastname@example.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.
Please Improve this article if you find anything incorrect by clicking on the "Improve Article" button below.