trace: a 0 b 1 1 trace: b 1 c 2 1 trace: c 2 a 0 1 trace: d 3 e 4 1 trace: e 4 f 5 1 trace: f 5 d 3 1 trace: 6 vertices in T, the six PQ lists: weight 999 vertex a 0 weight 999 vertex b 1 weight 999 vertex c 2 weight 999 vertex d 3 weight 999 vertex e 4 weight 999 vertex f 5 Starting new subtree with vertex a Adjusting for edge a 0 c 2 old 999 new 1 Adjusting for edge a 0 b 1 old 999 new 1 trace: 5 vertices in T, the six PQ lists: weight 999 vertex d 3 weight 999 vertex e 4 weight 999 vertex f 5 weight 1 vertex b 1 predecessor a 0 weight 1 vertex c 2 predecessor a 0 Included edge b a 1 trace: 4 vertices in T, the six PQ lists: weight 999 vertex d 3 weight 999 vertex e 4 weight 999 vertex f 5 weight 1 vertex c 2 predecessor a 0 Included edge c a 1 trace: 3 vertices in T, the six PQ lists: weight 999 vertex d 3 weight 999 vertex e 4 weight 999 vertex f 5 Starting new subtree with vertex d Adjusting for edge d 3 f 5 old 999 new 1 Adjusting for edge d 3 e 4 old 999 new 1 trace: 2 vertices in T, the six PQ lists: weight 1 vertex e 4 predecessor d 3 weight 1 vertex f 5 predecessor d 3 Included edge e d 1 trace: 1 vertices in T, the six PQ lists: weight 1 vertex f 5 predecessor d 3 Included edge f d 1 MSF weight is 4