pta 基本fraction分数类

下面是一个基本的 C++ 类实现，用于表示分数：

#include <iostream>

using namespace std;

class Fraction {
private:
    int numerator;   // 分子
    int denominator; // 分母

public:
    Fraction(int n, int d) {
        numerator = n;
        denominator = d;
    }

    Fraction operator+(Fraction const &obj) {
        int n = numerator * obj.denominator + obj.numerator * denominator;
        int d = denominator * obj.denominator;
        return Fraction(n, d);
    }

    Fraction operator-(Fraction const &obj) {
        int n = numerator * obj.denominator - obj.numerator * denominator;
        int d = denominator * obj.denominator;
        return Fraction(n, d);
    }

    Fraction operator*(Fraction const &obj) {
        int n = numerator * obj.numerator;
        int d = denominator * obj.denominator;
        return Fraction(n, d);
    }

    Fraction operator/(Fraction const &obj) {
        int n = numerator * obj.denominator;
        int d = denominator * obj.numerator;
        return Fraction(n, d);
    }

    void simplify() {
        int gcd = __gcd(numerator, denominator);
        numerator /= gcd;
        denominator /= gcd;
    }

    void display() {
        if (denominator == 1) {
            cout << numerator << endl;
        } else {
            cout << numerator << "/" << denominator << endl;
        }
    }
};

int main() {
    Fraction f1(2, 3);
    Fraction f2(3, 4);

    Fraction f3 = f1 + f2;
    f3.simplify();
    f3.display();

    Fraction f4 = f1 - f2;
    f4.simplify();
    f4.display();

    Fraction f5 = f1 * f2;
    f5.simplify();
    f5.display();

    Fraction f6 = f1 / f2;
    f6.simplify();
    f6.display();

    return 0;
}

这个类实现了加、减、乘、除四个运算符重载，并且包含了化简分数以及显示分数的方法。在主函数中，我们创建了两个分数对象 `f1` 和 `f2`，然后通过运算符重载来对它们进行加减乘除的操作，并且将结果化简后输出。