Its confused to explaing, but, this is what I amtrying to get.
Result: option 1: AX1 AX3 - has 2 random elements from @acc
option 2: AX1PB7 AX3PB6 - has 2 random from @acc and 2 random from @sec
option 3: AX1XC2 AX2CX8 - has 2 random from @acc and 2 random from @third
option 4: AX3PB6XC8 AX1PB6CX2 - has 2 random from @acc, 2 random elements from @sec and 2 random from @third
Comment on Re^2: Random number of elements from arrays
Often you can clear up confusion by being clearer about the context of what you are trying to do. Give us the bigger picture and we can more easily paint in the details.
Premature optimization is the root of all job security