state find_width
    return_if(`ln` != 10)
    `li1+sw`
    rewind()
    set_state(start)
end


state start
    return_if(`ln` != '0')

    `ln48-SN` # number
    `liSC` # coords

    find_path()
    `dlo+so`
    `[path count:]nn10an`

end

interrupt program_start

    # X: dynamic programming array
    # Y: have entry in above
    # Z: current visited

    `0so`

end


interrupt program_end
    
    `[out:]n10an`
    `lop`

end


function find_path

    `[path n=]nlNn[ c=]nlCn10an`

    # out of bounds
    if `lC` < 0 then
        `LCstLNst`
        return 0
    end


    # circular 
    #if array_get('Z', `lC`) == `li1+` then
    #    `[circle]n10an`
    #    `LCstLNst` # clear params
    #    return 0
    #end

    # mark with this index
    array_set('Z', `lC`, `li1+`)

    # already found the solution to this problem
    if array_get('Y', `lC`) == 1 then 
       `[cached]n10an`
       `LNst`
       return array_get('X', `LC`)
    end


    # if this is an endpoint
    if `lN` == 9 then 
        # set this entry as 1
        array_set('X', `lC`, 1)
        array_set('Y', `LC`, 1)

        `LNst` # pop params

        return 1
    end
    
    # start sum
    0

    # store wanted
    `lN49+S2`

    # top
    
    `lClw-S1` # calculate index
    # if this is the number we are looking for
    if `l1` >= 0 then 
        if array_get('I', `l1`) == `l2` then 

            `L1SC` # push new coord
            `l248-SN` # push new num

            # recurse
            find_path()

            `+`
        end
    end

    # right
    
    `lC1+S1` # calculate index
    # if this is the number we are looking for
    if `l1` > 0 then 
        if array_get('I', `l1`) == `l2` then 

            `L1SC` # push new coord
            `l248-SN` # push new num

            # recurse
            find_path()

            `+`
        end
    end

    # down
    
    `lClw+S1` # calculate index
    # if this is the number we are looking for
    if `l1` >= 0 then 
        if array_get('I', `l1`) == `l2` then 

            `L1SC` # push new coord
            `l248-SN` # push new num

            # recurse
            find_path()

            `+`
        end
    end


    # left
    
    `lC1-S1` # calculate index
    # if this is the number we are looking for
    if `l1` >= 0 then 
        if array_get('I', `l1`) == `l2` then 

            `L1SC` # push new coord
            `l248-SN` # push new num

            # recurse
            find_path()

            `+`
        end
    end


    # remove N and 2
    `LNstL2st`
    # mark as cached
    array_set('Y', `lC`, 1)
    # store sum in X (and return it)
    `dLC:X`
end