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Theme: Logical

Author/Opus: This is the 198th puzzle from our contributing puzzlemaster Grant Fikes.

Rules: Standard Cross the Streams rules. Also there are two windows in the upper left (blue) and lower right (red) of the grid. The cells in the same position in these windows must have the exact opposite shading.

Answer String: Enter the length in cells of each of the black segments from top to bottom for the marked columns, going in order from A to B to C to D and separating each entry with a comma.

Time Standards (highlight to view): Grandmaster = 3:30, Master = 5:00, Expert = 10:00.

Solution: PDF; a solution video is available here.

Note: Follow this link for other Cross the Streams. If you are new to this puzzle type, here are our easiest Cross the Streams to get started on.