@Override
public PancakeState initialState() {
PancakeState s = new PancakeState(this.numCakes);
System.arraycopy(this.init, 0, s.cakes, 0, numCakes);
s.h = this._countGaps(s.cakes, this.costFunction);
s.d = this._countGaps(s.cakes, COST_FUNCTION.UNIT);
if (this.k == 0) {
s.dNoGaps = s.d;
} else {
// Calc d without k
s.dNoGaps = this._countGaps(s.cakes, COST_FUNCTION.UNIT, false);
}
return s;
}
@Override
public State unpack(PackedElement packed) {
PancakeState state = new PancakeState(this.numCakes);
int index = this.numCakes - 1;
for (int i = packed.getLongsCount() - 1; i >= 0; --i) {
long current = packed.getLong(i);
int maxIterationIndex = this.packedCakesInSingleLong;
// In case of first iteration (starting from the end, maybe only part of the full coverage of
// pancakes is
// included inside the packed long - let's calculate this count
if (i == packed.getLongsCount() - 1) {
// E.g. if (numCakes=20; packedCakesInSingleLong=12 => maxIterationIndex=8)
// if (numCakes=15; packedCakesInSingleLong=15 => maxIterationIndex=0)
// if (numCakes=10; packedCakesInSingleLong=10 => maxIterationIndex=0)
int specificMaxIterationIndex = this.numCakes % this.packedCakesInSingleLong;
if (specificMaxIterationIndex > 0) {
maxIterationIndex = specificMaxIterationIndex;
}
}
for (int j = 0; j < maxIterationIndex && index >= 0; ++j) {
int p = (int) (current & (int) this.maskForSinglePancake);
current >>= this.bitsForSinglePancake;
state.cakes[index--] = p;
}
}
state.h = this._countGaps(state.cakes, this.costFunction);
state.d = this._countGaps(state.cakes, COST_FUNCTION.UNIT);
state.dNoGaps = this._countGaps(state.cakes, COST_FUNCTION.UNIT, false);
return state;
}
@Override
public State applyOperator(State state, Operator op) {
PancakeState pancakeState = (PancakeState) copy(state);
int pancakeOperator = ((PancakeOperator) op).value;
// Flip the top of the stack
pancakeState.flipTopStackPortion(pancakeOperator);
pancakeState.h = this._countGaps(pancakeState.cakes, this.costFunction);
pancakeState.d = this._countGaps(pancakeState.cakes, COST_FUNCTION.UNIT);
if (this.k == 0) {
pancakeState.dNoGaps = pancakeState.d;
} else {
// Calc d without k
pancakeState.dNoGaps = this._countGaps(pancakeState.cakes, COST_FUNCTION.UNIT, false);
}
return pancakeState;
}