Blocking flow

Input

1. A directed graph [math]\displaystyle{ G=(V,A) }[/math].
2. Source [math]\displaystyle{ s\in V }[/math] and target [math]\displaystyle{ t\in V }[/math].
3. An upper boud [math]\displaystyle{ u(a) }[/math] for each arc [math]\displaystyle{ a\in A }[/math].

Output

A Blocking flow [math]\displaystyle{ f }[/math].