My second condition would reject the additional element, as it would not be found in the input. have to be duplicated to However, I was lazy about the `|input|

My second condition would reject the additional element, as it would not be found in the input. have to be duplicated to However, I was lazy about the `|input| = |output|` constraints. With those constraints it would not be possible to omit elements from the input in the output.