| Trace | Node | Current state | Prefix alignment | Current cost |
| σ1 | | ([p1], s0) | <> | 0 | | ([p2], sa) | <(a, t1)> | 0 | | ([p3], ) | <(a, t1), (b, t2)> | 0 | | ([p4], ) | <(a, t1), (b, t2), (>>, t4)> | 1 |
| σ2 | | ([p1], s0) | <> | 0 | | ([p2], s0) | <(>>, t1)> | 1 | | ([p3], ) | <(>>, t1), (b, t2)> | 1 | | ([p4], ) | <(>>, t1), (b, t2), (d, t4)> | 1 |
| σ3 | | ([p1], s0) | <> | 0 | | ([p2], sa) | <(a, t1)> | 0 | | ([p2], sa) | <(a, t1), (a, >>)> | 1 | | ([p3], ) | <(a, t1), (a, >>), (b, t2)> | 1 | | ([p4], ) | <(a, t1), (a, >>), (b, t2), (>>, t4)> | 2 |
| σ4 | | ([p1], s0) | <> | 0 | | ([p2], sa) | <(a, t1)> | 0 | | ([p3], ) | <(a, t1), (b, t2)> | 0 | | ([p4], ) | <(a, t1), (b, t2), (d, t4)> | 0 |
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