File with minimum energy
1 10 20 30 40
2 20 30 45 50

Another file
1 10 11 50 50
2 20 21 60 60

Do you want:
R 11 30
R 21  5

30 = (50 + 50) - (30 + 40)
 5 = (60 + 60) - (45 + 50)
I just put 'R' since I don't know what that value should be.