Would 0011 Sally ever appear more than once? And if so, would the output contain two listings of Sally, or one?

0011 Sally
0011 Sally
0011 Sally
# This? -------------
0011 ---> 3
Sally
Sally
Sally
# Or this? ----------
0011 ---> 3
Sally
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So the first question is what to do with collisions of the same name within the same prefix.

Also, what is the min and max for the numeric range? How many distinct numeric prefixes are there, and does the maximum prefix change over time?

I'm just wondering, as the solution may be different if we know more about the input data.