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+⍝ count contiguous blocks

+contig←{

+    G←⍵                             ⍝ input array

+    ⍝ do floodfill with 0s on G starting at ⍵

+    flood←{

+        adj←⍵∘+¨(+,-)↓∘.=⍨⍳3       ⍝ adjacent coordinates...

+        adj←(adj∊,⍳⍴G)/adj         ⍝ ...which are within the figure...

+        adj←(1=G[adj])/adj         ⍝ ...and are marked

+        G[⊂⍵]←0                    ⍝ set current position to zero

+        0=⍴adj:⍬                   ⍝ if no adjacent ones, stop

+        ∇¨adj                      ⍝ recurse

+    }

+    ⍝ find coordinates of ones

+    ones←(,G)/,⍳⍴G

+    0=⍴ones:0  ⍝ no ones = no figures

+    ⍝ remove figure starting at first one

+    _←flood⊃ones

+    ⍝ the result is 1 + the amount of figures in the modified array

+    1+∇G

+}

+⍝ read a block from the interactive input

+read←{

+    ln←{⍞}

+    dm←{

+        0=⍴in←⍺⍺⍬:⍬

+        (⊂in),∇⍬

+    }

+    '1'=↑↑↑ln dm dm⍬

+}

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