8×4
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L     D←| #####  |12345678|10000012|        |        |
«»⍳  ÷×A|     |*^|     √∧v|11222221|        |        |
{}=≠ -+ |⍵⍺≥>    |  ≤<  ∨ |33222222|        |        |
()/\ ⍴,¨|[]⌿⍀  ⍪ |########|33222222|        |        |