/**
* For the small solution, an example of Integer Linear Programming
*
* @param in
* @return
*/
public String handleCase2(InputData in) {
List<Double> zeroCoef = Collections.nCopies(in.N, 0d);
// 8 0 1 2 0
// assigned.put(2, 1);
// assigned.put(3, 2);
Stack<Simplex> assignementsToTry = new Stack<>();
Simplex s2 = new Simplex(in.N);
addConstraints(s2, new HashMap<Integer, Integer>(), in);
assignementsToTry.add(s2);
Map<Integer, Integer> assigned = new HashMap<Integer, Integer>();
int tries = 0;
while (!assignementsToTry.isEmpty()) {
++tries;
Simplex simplex = assignementsToTry.pop();
log.info("Tries {}", tries);
List<Double> solution = Lists.newArrayList();
boolean f = false; // simplex.doPhase1(solution);
if (!f) {
// return String.format("Case #%d: Impossible", in.testCase, solution.subList(0, in.N));
continue;
}
int smallestNonIntIndex = -1;
double smallest = Double.MAX_VALUE;
List<Integer> solInt = Lists.newArrayList();
for (int solIndex = 0; solIndex < in.N; ++solIndex) {
double sol = solution.get(solIndex);
double solAsInt = Math.rint(sol);
if (Math.abs(solAsInt - sol) > 1e-5 && sol < smallest) {
smallestNonIntIndex = solIndex;
smallest = solution.get(solIndex);
}
if (assigned.containsKey(solIndex)) {
solInt.add(assigned.get(solIndex));
} else {
solInt.add((int) Math.rint(solution.get(solIndex)));
}
}
if (smallestNonIntIndex == -1) {
return String.format("Case #%d: %s", in.testCase, Joiner.on(' ').join(solInt));
} else {
Simplex try1 = new Simplex(simplex);
Simplex try2 = new Simplex(simplex);
double nonIntSolution = solution.get(smallestNonIntIndex);
Preconditions.checkState(nonIntSolution >= 0d);
double intSolutionLB = Math.ceil(nonIntSolution);
double intSolutionUP = Math.floor(nonIntSolution);
List<Double> coeffsTry1 = Lists.newArrayList(zeroCoef);
List<Double> coeffsTry2 = Lists.newArrayList(zeroCoef);
coeffsTry1.set(smallestNonIntIndex, 1d);
coeffsTry2.set(smallestNonIntIndex, 1d);
try2.addConstraintLTE(coeffsTry2, intSolutionUP);
try1.addConstraintGTE(coeffsTry1, intSolutionLB);
assignementsToTry.add(try1);
assignementsToTry.add(try2);
}
}
return String.format("Case #%d: Impossible", in.testCase);
/*if (1==1)
return String.format("Case #%d: Impossible", in.testCase);
List<Double> solution = Lists.newArrayList();
List<Double> solutions = solution.subList(0, in.N);
log.info("Solutions {}", solutions);
List<Fraction> solutionFra = Lists.transform(solutions, new Function<Double,Fraction>(){
public Fraction apply(Double arg) {
return new Fraction(arg);
}
});
long lcm = 1;
for(Fraction fr : solutionFra) {
if (fr.getNumerator() == 0)
continue;
lcm = LongMath.checkedMultiply(lcm, fr.getDenominator() / LongMath.gcd(lcm, fr.getDenominator()));
}
List<Integer> solInt = Lists.newArrayList();
for(Fraction fr : solutionFra) {
solInt.add( Ints.checkedCast(LongMath.checkedMultiply(lcm, fr.getNumerator()) / fr.getDenominator()));
}
return String.format("Case #%d: %s", in.testCase, Joiner.on(' ').join(solInt));*/
}
private boolean addConstraints(Simplex s, Map<Integer, Integer> assigned, InputData in) {
List<Double> zeroCoef = Collections.nCopies(in.N, 0d);
for (int i = 0; i < in.N - 1; ++i) {
int max = in.highest[i] - 1;
for (int j = i + 1; j < max; ++j) {
List<Double> coeffs = Lists.newArrayList(zeroCoef);
coeffs.set(max, (double) j - i);
coeffs.set(i, (double) max - j);
coeffs.set(j, (double) i - max);
double rhs = 1;
int cof = 0;
for (int all = 0; all < in.N; ++all) {
if (coeffs.get(all) != 0 && assigned.containsKey(all)) {
rhs -= coeffs.get(all) * assigned.get(all);
coeffs.set(all, 0d);
++cof;
}
}
if (cof == 3) {
Preconditions.checkState(rhs >= 0);
}
s.addConstraintGTE(coeffs, rhs);
log.debug("Eq : {}Y{} + {}Y{} + {}Y{} >= 1", j - i, max, max - j, i, i - max, j);
}
for (int j = max + 1; j < in.N; ++j) {
List<Double> coeffs = Lists.newArrayList(zeroCoef);
coeffs.set(max, (double) j - i);
coeffs.set(i, (double) max - j);
coeffs.set(j, (double) i - max);
double rhs = 0;
int cof = 0;
for (int all = 0; all < in.N; ++all) {
if (coeffs.get(all) != 0 && assigned.containsKey(all)) {
rhs -= coeffs.get(all) * assigned.get(all);
coeffs.set(all, 0d);
++cof;
}
}
if (cof == 3 && rhs < 0) {
return false;
}
s.addConstraintGTE(coeffs, rhs);
log.debug("Eq : {}Y{} + {}Y{} + {}Y{} >= 0", j - i, max, max - j, i, i - max, j);
}
}
return true;
}
