Operator Overloading in C++

This is a simple program in c++ in which the operators will be overloaded. In this program add,sub mul and div operator is overloaded !

Screenshots:

The Program:

#include<iostream>
using namespace std;
class mat
{
 public:
  int a;
  mat(int val)
  {
   a=val;
  }
  mat()
  {
  }
  mat operator +(mat &b)
  {
   return mat(a+b.a);
  }
  mat operator -(mat &b)
  {
   return mat(a-b.a);
  }
  mat operator /(mat &b)
  {
   return mat(a/b.a);
  }
  mat operator *(mat &b)
  {
   return mat(a*b.a);
  }
  void disp()
  {
   cout<<a<<endl;
  }
};

class inc
{
 public:
  int x;
  inc (int val)
  {
   x=val;
  }
  friend inc operator ++(inc &,int);
  void disp()
  {
   cout<<x<<endl;
  }
};
inc operator ++(inc &a,int)
{
 return inc(a.x+1);
}
int main()
{
 mat a1(4),a2(6),a3;
 a3=a2+a1;
 a3.disp();
 a3=a2-a1;
 a3.disp();
 a3=a2*a1;
 a3.disp();
 a3=a2/a1;
 a3.disp();
 inc i1(5);
 i1++;
 i1.disp();
}

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