Matrix multiply c++

Hello all
I'm a newbie in C++... Could you please help me solve this calculation with C++: I have two matrix in two text files:

File A:

10001 14462 14382 14459
10002 14304 14382 14462
10003 14298 14382 14304
10004 14459 14382 14298
10005 14473 14386 14462
File B:

1446 2 1 5
14382 5 9 8
14459 6 9 5
14304 5 2 1
14462 7 5 4
14298 5 4 7
14473 2 3 4
we have A11=1001; A21=1002...and I want to create a new matrix

AA=
10001 (v14462-v14382) (v14382-v14459) (v14459-v14462)
10002 (v14304-v14382) (v14382-v14462) (v14462-V14304)
10003 ...............................................
10004 ...............................................
10005 ...............................................
where v14462 is a vector which could get from file B, it means vector v14462=[2 1 5]; same for v14382, v14459.....

Thank you all very much! Happy christmas and happy new year!