why we use operator overloading in c++ code example

Example 1: c++ operator overloading

// money.h -- define the prototype
class Money
{
   public:
      Money & operator += (const Money &rhs);
}

// money.cpp -- define the implementation
Money& Money :: operator += (const Money &rhs)
{
   // Yadda Yadda
  
   return *this;
}

Example 2: Operator overloading in C++ Programming

#include <iostream>
using namespace std;

class Test
{
   private:
      int count;

   public:
       Test(): count(5){}

       void operator ++() 
       { 
          count = count+1; 
       }
       void Display() { cout<<"Count: "<<count; }
};

int main()
{
    Test t;
    // this calls "function void operator ++()" function
    ++t;    
    t.Display();
    return 0;
}

Example 3: c++ over load operator

// This will substract one vector (math vector) from another
// Good example of how to use operator overloading

vec2 operator - (vec2 const &other) {
    return vec2(x - other.x, y - other.y);
}

Example 4: overload the >> operator in c++

istream &operator>>( istream  &input, Class_Name &c )