Dynamic Enumeration Tree

abcd  { }

abc  {r1}

r1r2  {c}

r1 {bc}

ab {r1}

a {r1r2}

ac {r1r2}

acd { r2}

a {r1r2}

r2 {cd}

ad  {r2}

r1 {c}

r1r3 { c}

b {r1r3}

{ }

r3 { c}

abc: {r1} ac: {r1r2} acd: {r2}

c {r1r2r3}

r2  {d }

d {r2r4}

Feature enumeration to Row enumeration