Perl version 5.008008
1 plus 2
AX plus BY
X plus BY
DA plus EBCDEF
A plus EBCDEF
EBCDEF plus FGH
BCDEF plus FGH
CDEF plus FGH
DEF plus FGH
EF plus FGH
F plus FGH
H plus I
I plus J
J plus K
7 plus Z