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Checkpoint: Collections + Control Flow

beginner20 min readLesson 23 of 169

Nested data, loops, and decisions combined into one report program.

Checkpoint: Collections + Control Flow

Modules 5–6 in one program: walk a nested structure, accumulate a result, and branch on what you find. This is the shape of a real data report — and the exact skill the file-processing modules will ask you to apply.