public static LpSolve conv2MinCostLP(
int[][] cs, int[][] cost, int[][] map, int s, int t, double objective)
throws LpSolveException {
int E = cntE(cs);
int V = cntV(cs);
LpSolve solver = conv2LPBase(cs, s, t, map, V, E);
solver.strAddConstraint(objStr(cs, E, map, s), LpSolve.EQ, objective);
solver.setMinim();
solver.setLpName("Converted min cost flow");
int[] constr = new int[E];
for (int from = 0; from < cs.length; from++) {
for (int to = 0; to < cs.length; to++) {
if (cs[from][to] != 0) {
constr[map[from][to]] = cost[from][to];
}
}
}
solver.strSetObjFn(constrStr(constr));
return solver;
}
public static LpSolve conv2LPBase(int[][] cs, int s, int t, int[][] map, int V, int E)
throws LpSolveException {
LpSolve solver = LpSolve.makeLp(0, E);
// GENERATE capacity constraints
for (int from = 0; from < cs.length; from++) {
for (int to = 0; to < cs.length; to++) {
if (cs[from][to] != 0) {
int[] constr = new int[E];
constr[map[from][to]] = 1;
solver.strAddConstraint(constrStr(constr), LpSolve.LE, cs[from][to]);
}
}
}
// GENERATE in-out-equalities
for (int u = 0; u < cs.length; u++) {
if (u != s && u != t) {
int[] constr = new int[E];
for (int v = 0; v < cs.length; v++) {
if (cs[v][u] != 0) {
constr[map[v][u]] = 1;
}
if (cs[u][v] != 0) {
constr[map[u][v]] = -1;
}
}
solver.strAddConstraint(constrStr(constr), LpSolve.EQ, 0);
}
}
return solver;
}
public static LpSolve conv2LP(int[][] cs, int s, int t, int[][] map) throws LpSolveException {
int E = cntE(cs);
int V = cntV(cs);
LpSolve solver = conv2LPBase(cs, s, t, map, V, E);
// GENERATE objective function
solver.strSetObjFn(objStr(cs, E, map, s));
// other options
solver.setMaxim();
solver.setLpName("Converted max flow");
// solver.setVerbose(3);
return solver;
}
