A(13): [ES:  0  EF: 13 / LS:  0  LF: 13] total float =  0
   B( 6): [ES: 13  EF: 19 / LS: 25  LF: 31] total float = 12
   C( 6): [ES: 19  EF: 25 / LS: 31  LF: 37] total float = 12
   D( 6): [ES: 25  EF: 31 / LS: 37  LF: 43] total float = 12
   E(10): [ES: 13  EF: 23 / LS: 13  LF: 23] total float =  0
   F(20): [ES: 23  EF: 43 / LS: 23  LF: 43] total float =  0
   G( 8): [ES: 13  EF: 21 / LS: 23  LF: 31] total float = 10
   H(12): [ES: 21  EF: 33 / LS: 31  LF: 43] total float = 10
   I( 5): [ES: 43  EF: 48 / LS: 43  LF: 48] total float =  0

All paths:
ABCDI: 36
AEFI: 48
AGHI: 38

Critical path: AEFI