Please choose the correct ending to complete the given sentence: Computers and Electronics: [header] How to hack a candy machine [title] Put double stick tape on the coin. [step] Use strong double stick tape to attach the coin to the knob. If the tape is strong enough, the coin won't drop or be pulled off as intended, so it can be reused for multiple pieces of candy.

Ending1: [substeps] You may need to shave down a bit to get a strong, sticky sticky covering that you can attach to the coin. You can use scissors to cut the sticky tape into strips that are length 1 ¼ inch (1 centimeter) wide. Ending2: [title] Try turning the knob back and forth. [step] This will only work on a low-quality machine or a machine that has not been properly put together, so just try this once and move on if it doesn't work. Ending3: [title] Use' snake' tape if you want a more complex design. [step] If you want a deeper design, use a specially-made snake. Ending4: Ensure that the small knob that connects the candy machine to the wall is secure. [title] Write down the name and the billing code that is on the coin.

Answer format: ending1/ending2/ending3/ending4