A(B,C) A(B(D(H,I),E(J,K)),C(F(L,^),G)) A(^,B(^,C(^,D))) A(B(D(^,G),^),C(E,F)) T
A(B,C): 先序:ABC 中序:BAC 后序:BCA A(B(D(H,I),E(J,K)),C(F(L,^),G)): 先序:ABDHIEJKCFLG 中序:HDIBJEKALFCG 后序:HIDJKEBLFGCA A(^,B(^,C(^,D))): 先序:ABCD 中序:ABCD 后序:DCBA A(B(D(^,G),^),C(E,F)): 先序:ABDGCEF 中序:DGBAECF 后序:GDBEFCA T: 先序:T 中序:T 后序:T