Sasha

function iff (x,y,z)
if a[x][y][z]==1 then
turtle.select(1)
elseif a[x][y][z]==2 then
turtle.select(2)
elseif a[x][y][z]==3 then
turtle.select(3)
elseif a[x][y][z]==4 then
turtle.select(4)
elseif a[x][y][z]==5 then
turtle.select(5)
elseif a[x][y][z]==6 then
turtle.select(6)
elseif a[x][y][z]==0 then
turtle.select(16)
end
end

a = {
    {
        {0,1,1,1,1,1,0},
        {0,1,0,0,0,1,0},
        {0,1,0,0,0,1,0},
        {0,1,0,0,0,1,0},
        {0,2,2,1,2,2,0}
    },
    {
        {0,1,1,1,1,1,0},
        {0,1,0,0,0,1,0},
        {0,1,0,0,0,1,0},
        {0,1,0,0,0,1,0},
        {0,1,1,3,1,1,0}
    },
    {
        {0,1,1,1,1,1,0},
        {0,1,0,0,0,1,0},
        {0,1,0,0,0,1,0},
        {0,1,0,0,0,1,0},
        {0,1,3,1,3,1,0}
    },
    {
        {0,1,1,1,1,1,0},
        {0,1,0,0,0,1,0},
        {0,1,0,0,0,1,0},
        {1,1,0,0,0,1,1},
        {0,1,1,1,1,1,0}
    },
    {
        {0,0,0,0,0,0,0},
        {0,0,0,0,0,0,0},
        {0,0,0,0,0,0,0},
        {1,2,1,0,1,2,1},
        {0,0,0,0,0,0,0}
    },
    {
        {0,0,0,0,0,0,0},
        {0,0,0,0,0,0,0},
        {0,0,0,0,0,0,0},
        {4,4,0,0,0,4,4},
        {0,0,0,0,0,0,0}
    }
}


turtle.up()

for x=1, #a do
  for y=1, #a[x] do
    for z=1, #a[x][y] do
      iff(x,y,z)
      turtle.placeDown()
      turtle.forward()
    end

turtle.turnRight()
turtle.forward()
turtle.turnRight()

for y = 1,#a[x][y] do
turtle.forward()
end

turtle.turnRight()
turtle.turnRight()
end

turtle.turnLeft()
for y = 1,#a[x] do
turtle.forward()

end
turtle.turnRight()
turtle.up()
end