using System;

using System; 

public class Rational

 {     public int num;     public int denum;     public double dec;     

     public Rational(int n, int d)

   {this.num = n;this.denum = d;} 

    public Rational(Rational r)//копиращ конструктор

     {this.num = r.num;this.denum = r.denum;     }

     public void Add(Rational r)

     {         this.num = this.num * r.denum + r.num * this.denum;

         this.denum = r.denum*this.denum;         int g=GCD(num, denum);

        this.num=this.num/g;         this.denum=this.denum/g;

         Console.WriteLine(this.num+"/"+this.denum); 

    } 

    public void Sub(Rational r) 

    {         this.num = this.num * r.denum - r.num * this.denum;   

      this.denum = r.denum*this.denum;         int g=GCD(num, denum);

    this.num=this.num/g;         this.denum=this.denum/g; 

    }    

 public void Mult(Rational r)  

   {         this.num = this.num*r.num;         this.denum = this.denum*r.denum; 

int g=GCD(num, denum);         this.num=this.num/g;  

       this.denum=this.denum/g; 

    }  

   public void Div(Rational r) 

    {         this.num = this.num*r.denum;         this.denum = this.denum*r.num; 

int g=GCD(num, denum);         this.num=this.num/g;   

      this.denum=this.denum/g; 

    }   

  public int Compare(Rational r) 

    {         if(this.num*r.denum > r.num*this.denum) return 1;  

       if(this.num*r.denum < r.num*this.denum) return -1; 

        return 0;   

  }  

   public void Dec() 

    {         this.dec = (double)this.num/ this.denum;     } 

public void Print(Rational r) 

    {         this.dec = (double)this.num/ this.denum; 

        Console.WriteLine(this.dec);         normPrint();

     }     

public void normPrint() 

    {         if (this.denum==1) Console.WriteLine(this.num);  

       else if(this.num==0) Console.WriteLine("0"); 

        else Console.WriteLine(this.num+" / "+this.denum);

     }

private int GCD(int a, int b)  

   {         int tmp, r;  

       if(a<b) {tmp=a; a=b; b=tmp;}  

       while(b!=0)  

       {r=a%b ;a=b; b=r;}  

       return a;

   } } 

public class Program

 {     public static void Main()  

   {         //Rational rc = new Rational();

         //rc.num = 1234; 

        //rc.denum = 2345; 

        //rc.Dec();    

     //rc.Print(rc);  

       int xnum, xdenum,ynum, ydenum;

     Console.WriteLine("Въведи числител 1");

     xnum = int.Parse(Console.ReadLine());

     Console.WriteLine("Въведи знаменател 1");

       xdenum = int.Parse(Console.ReadLine());

      Console.WriteLine("Въведи числител 2");

        ynum = int.Parse(Console.ReadLine());

     Console.WriteLine("Въведи знаменател 2");

     ydenum = int.Parse(Console.ReadLine()); 

        Rational x = new Rational(xnum,xdenum);  

       Rational y = new Rational(ynum,ydenum); 

Rational a = new Rational(x); a.Add(y); a.Print(a);  

       //Console.WriteLine(xnum+"/"+xdenum+" "+ynum+"/"+ydenum); 

Rational s = new Rational(x); s.Sub(y); s.Print(s);  

Rational m = new Rational(x); m.Mult(y); m.Print(m);

Rational d = new Rational(x); d.Div(y); d.Print(d); 

        int c = x.Compare(y);  

       if(c==1) Console.WriteLine("x>y");  

       else if(c==-1) Console.WriteLine("x<y");  

       else Console.WriteLine("x=y");     } }

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