in reply to Re^2: Using indexing for faster lookup in large file
in thread Using indexing for faster lookup in large file

The data is sorted lexicographically on the first number.

You mean like this?

C:\Users\HomeAdmin>perl -E"@s = 1..30; say for sort @s"
1
10
11
12
13
14
15
16
17
18
19
2
20
21
22
23
24
25
26
27
28
29
3
30
4
5
6
7
8
9

[download]

Also, what are the smallest and largest keys ("first numbers") in the file?

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