Lab12 修改中

public class Fraction {
private double numerator , denominator ;
Fraction(){
numerator = denominator = 0;
}

Fraction(double numerator , double denominator){
this.numerator = numerator;
this.denominator = denominator;
}

Fraction ( Fraction f ){
this.numerator = f.numerator ;
this.denominator = f.denominator;
}

public static Fraction add(Fraction f1,Fraction f2) {
Fraction f3 = new Fraction();
if(f1.numerator == 0){
f3.numerator = f2.numerator ;
f3.denominator = f2.denominator ;
return f3;
}

else if(f2.numerator == 0){
f3.numerator = f1.numerator ;
f3.denominator = f1.denominator ;
return f3;
}

else if(f1.denominator ==0 f2.denominator ==0){
System.out.println("分母不可為0");
return f3;
}
else {
f3.denominator = f2.denominator * f2.denominator ;
f3.numerator = f1.numerator*f2.denominator + f2.numerator*f1.denominator ;
return f3;
}
}
public static double showN(Fraction f3){
return f3.numerator; }
public static double showD(Fraction f3){
return f3.denominator;} }
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public class Demo {
public void main(String[] args){
Fraction Fraction1 = new Fraction(2,3),
Fraction2 = new Fraction(3,4),
Fraction3 = new Fraction();
Fraction3=Fraction.add(Fraction1,Fraction2);
System.out.println(Fraction.showN(f3) + "/" + Fraction.showD(f3)); }}