30seconds/FractionOperator.java at master · ict/30seconds · GitHub

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importjava.util.Random;

publicclassFractionOperatorextendsOperator {

privateintnumerator;
privateintdenominator;

publicFractionOperator(Difficultydiff, Randomrand) {
super(diff, rand);
shuffle();
	}

publicOperatorcloneThis() {
FractionOperatorn = newFractionOperator(this.diff, this.rand);
n.numerator = this.numerator;
n.denominator = this.denominator;
returnn;
	}

publicvoidshuffle() {
// We need to cheat for this operator to be useful, so no real shuffling here
numerator = 0;
denominator = 0;
	}

publicbooleanworksForInput(intin) {
// find a denominator
denominator = 0;
for (inti = 12; i > 2; --i) {
if (in % i == 0)
denominator = i;
if (rand.nextInt(100) < 60)
break;
 }

// fail?
if (denominator == 0) {
returnfalse;
 }

// use a numerator?
if (rand.nextBoolean()) {
numerator = rand.nextInt(denominator - 1) + 2;
 } else {
numerator = 1;
 }

returntrue;
	}

publicintgetOutput() {
returnprev.getOutput() * numerator / denominator;
	}

publicStringtoString() {
if (numerator == 1) {
if (denominator == 2)
return"halbieren";
return"durch " + denominator;

 } else {
return"" + numerator + " / " + denominator + " davon";
 }
	}

publicStringtoTexString() {
if (numerator == 1) {
if (denominator == 2)
return"halbieren";
return"durch " + denominator;

 } else {
return"$\\frac{" + numerator + "}{" + denominator + "}$ "+ " davon";
 }
	}
}