# [1+](https://esolangs.org/wiki/1%2B), 10 bytes

```
."#:[#":1#
```

Yay for comment abuse in a normal challenge (instead of a source-layout or polyglot one)! In 1+, the `[` character that begins a comment is actually an instruction so it can be skipped with the goto command `#`.

For input 0:

```
.          Take input
 "#        Jump to the 0th hash tag
   ：      Output 0
    [      Comment the rest of the program out
```

For input 1:
```
.          Take input
 "#        Jump to the 1th hash tag
     #     The 1th hash tag
      ":   Duplicate and output
        1# Jump to the 1th hash tag
```

I can replace the `1` with `"` as well so that we get a 1+ program without a `1` instruction... Wow!

## Naive solution, 14 bytes
```
.1##":"1+1<1+#
```

A simple do-while loop.