top:200:100
 1: 100 foo:100
 2: 100
 3: 2
 4: 100
 1: foo:100
    2: 100
    3: 100 bar:100
    4: 100
 3: bar:2
    1: 2
    2: 2
foo:200:150
 2: 150
 3: 150  bar:150
 4: 150
bar:450:300
 1: 300 baz:300
 2: 300
 3: 300