Read file into 2D array
Borders are visible
    Border rules -
        -All Array[0,X]
        -All Array[array.length-1, X]
        -All Array[X, 0]
        -All Array[X, array.length-1]
For non-border squares
    -checkNorth
    -checkSouth
    -checkEast
    -checkWest
    For any trees taller than subject tree between subject tree and border
Get count of