Person: What do you do?
Me: I am a computer science professor.
Person: I have a problem with my PC, can you fix it?
Me: No, I don’t think I can do that.
Person: You will not fix my PC?
Me: I cannot fix my PC, let alone yours.
Person: Then what exactly do you do?
Me: I study algorithms.
Person: Oh, I know that.
Me: Really?
Person: Yes! I learnt logarithms in high school.
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Come from here.

The following generic 0-1 programming form can be solved by finding a minimum-cut of a bipartite directed graph. Max{Sigma{A(i)*X(i)}+Sigma{B(i)*Y(i)}-Sigma{C(i,j)*X(i)*Y(j)}} (C(i,j)>0).
To construct the network, first construct vertices one source S, one destination T, the left vertex set {X(1),X(2),...} and the right vertex set {Y(1),Y(2),...}, and add directed edges as the following rules:

• For each A(i)>0, add S-->X(i) with capacity A(i).  (X(i)=1 <===> S-->X(i) not in the cut)
  
• For each A(i)<0, add X(i)-->T with capacity -A(i).
• For each B(i)>0, add Y(i)-->T with capacity B(i). (Y(i)=1 <===> Y(i)-->T not in the cut)
  
• For each B(i)<0, add S-->Y(i) with capacity -B(i).
  
• For each C(i,j)>0, add X(i)-->Y(j) with capacity C(i,j).