// Push-relabel methods
// Push() pushes flow forwards, or decreases incoming flow
private void push(Vertex u, Vertex v) {
// System.out.println("Pushing from " + u + " to " + v);
int excess = u.getExcess();
int residualCapacity = getResidualCapacity(u, v);
assert (excess > 0) : "Excess <= 0";
assert (residualCapacity > 0) : "Resid capacity <= 0";
assert (u.getHeight() == v.getHeight() + 1) : "Height of u != height of v + 1";
int changeInFlow = excess < residualCapacity ? excess : residualCapacity;
if (flowsForward(u, v)) {
addToFlow(u, v, changeInFlow);
} else {
addToFlow(v, u, -changeInFlow);
}
u.addToExcess(-changeInFlow);
v.addToExcess(changeInFlow);
}
