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# [Vyxal](https://github.com/Vyxal/Vyxal) `o`, 5 bytes

```
~$","
```

[Try it Online!](https://lyxal.pythonanywhere.com?flags=o&code=~%24%22%2C%22&inputs=3%0A4&header=&footer=)

I'd say this counts, because `$` is quite literally "swap the top two items on the stack".

## Explained

```
~$","
~$    # Swap the top two items, but peek instead of pop
  ",  # pair and output
    " # pair what remains and output with the `o` flag
```

But if variables are absolutely needed:

## [Vyxal](https://github.com/Vyxal/Vyxal) `o`, 29 bytes

```
→x→y",←y→temp←x→y←temp→x←y←x"
```

[Try it Online!](https://lyxal.pythonanywhere.com?flags=o&code=%E2%86%92x%E2%86%92y%22%2C%E2%86%90y%E2%86%92temp%E2%86%90x%E2%86%92y%E2%86%90temp%E2%86%92x%E2%86%90y%E2%86%90x%22&inputs=3%0A4&header=&footer=)

## Explained

```
→x→y",←y→temp←x→y←temp→x←y←x"
→x→y                          # put the two inputs into x and y
    ",                        # print [y, x]
      ←y→temp                 # temp = y
             ←x→y             # y = x
                 ←temp→x      # x = temp
                        ←y←x" # print [y, x] (now swapped)
```