Level 0,foo=0
    Level 1,foo=0
    Level 2,foo=0
    Level 3,foo=0
    Level 4,foo=0
    Level 5,foo=0
    Level 5 done, foo=1
    Level 4 done, foo=1
    Level 3 done, foo=1
    Level 2 done, foo=1
    Level 1 done, foo=1
    Level 0 done, foo=1