Minesweeper←{
     (⎕IO ⎕ML)←1
⍝ Example input: 5 10⍴'×   × ××××         ×    × × ×    ××     ×   ×    ×'
     CellCount←{
    ⍝ A cell is a 3 by 3 area
         c←'×'=,⍵   ⍝ 1 is a mine, 0 is not
         5⊃c:'×'    ⍝ Middle is a mine?
         +/c        ⍝ Else count mines in cell
     }
     CellCount⌺3 3⊢⍵
 }