Hash Table 2D

Source:
[codebox]$h = {
A => {T=>5,A=>4,G=>3},
T => {A=>3,A=>9,G=>7},
C => {A=>2,A=>6,G=>8},
G => {A=>1,A=>4,G=>9},
};
print $h->{A}{T};[/codebox]
Output:
[src]5[/src]