OJ Board

I have spend 3 weeks on this problem....
I implement a BigInteger class to solve this problem....but it's too slow...
I think there must be an effective algorithm to solve this problem...
I almost spent all of my time on this....
Can anyone please give me a hint,please??
Thank you very much

cplusplus wrote:I have spend 3 weeks on this problem....
I implement a BigInteger class to solve this problem....but it's too slow...
I think there must be an effective algorithm to solve this problem...
I almost spent all of my time on this....
Can anyone please give me a hint,please??
Thank you very much

Thx, everyone
I have solved this problem
I found my BigInt is to slow in operator+=
after I modify it, I get AC(PE)
Thx for your help