Multidimensional Arrays In PL / SQL

I have to create a function which takes in 3 parameters as varchar2(SQL,From,Replace)

1) SQL is the actual SQL
2) Find is the table name to find
3) Replace is the table name to replace the found table.

Moreover there are 19 sets of Find,Replace and the above function loop through all the 19 sets to replace all the tablename in FInd with Replace. I could write the function but the problem is how do i define these sets of table names.

I tried define the tablenames as
Scrpt(1,1) = "PS_CGF_TBL"
Script(1,2)= "PS_CGF_C_TBL"
...
...
Script(19,1) = "PS_CGF_AC_TBL"
Script(19,2) = "PS_CGF_XX_TBL"

and then tried to loop it by declaring an integer as index as

For Index = 1 To 19
string = ReplaceAll(SQL, Script(Index, 1), Script(Index, 2))
Next.

I am getting error in declaring the table names.