IN JAVA

It is known that in the BCH(10,6) code, within 1 million possible numbers, only about 680000 of them are valid numbers. That is, the remaining 320000 are unusable numbers. These numbers are unusable because we have to abandon numbers which generate 10s in their parity checking part. Design an BCH(10,6) which utilises unusable numbers. Assume that we can either drop the double error correction requirement for those unusable numbers, or make the code length longer. You must explain how the coding method works, why it works, and what both the gains and the drawbacks are.