Computer Science: Programming, step by step

All lessons, part by part

1. 6.1 Syntax, run-time and logic errors
2. 6.2 Find a bug by tracing and printing
3. 6.3 What an exception is
4. 6.4 Catch and recover
5. 6.5 Validate before use
6. 6.6 Design test cases: normal, boundary, invalid
7. 6.7 Open, read, closenot yet
8. 6.8 Line by linenot yet
9. 6.9 Parse delimited lines into a list or tablenot yet
10. 6.10 Convert fields before usenot yet
11. 6.11 Write and appendnot yet
12. 6.12 When the file is missingnot yet
13. 6.13 Absolute and relative pathsnot yet
14. 6.14 Capstone: read a CSV, compute, write a summarynot yet

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Lesson 6.4 · Put the lines in order

Ask until it is a number

Python or Java