Given the next structure that represents a data table
[
[foo:42, baz:7],
[foo:45, bar:8, baz:9],
]
N rows, M items in a row, an item is <label>:<value>
Return a new structure with null values for items with no label e.g. constant row length.
[
[foo:42, bar:7, baz:null],
[foo:45, bar:8, baz:9],
]
labels can arbitrary repeat e.g.:
[
[foo:42, foo:99, bar:7, foo:77],
[foo:45, baz:9, baz:9, bar:8, baz:9, baz:10],
]
the consequence of labels in output can arbitrary.
Limitations
N < 10^6, M < 10^6