CODE EXAMPLE FOR CPP

overload subscript operator cpp

// It is idiomatic to provide couple of overloads of the operator[] function
// 		- one for const objects and one for non-const objects.
// The return type of the const member function can be a const& or
// just a value depending on the object being returned while the return type
// of the non-const member function is usually a reference.

struct Heap{
    int H[100];
    int operator [] (int i) const {return H[i];}
    int& operator [] (int i) {return H[i];}
};

//This allows you to modify a non-const object using the array operator...

Heap h1;
h1[0] = 10;

//...while still allowing you to access const objects.

Heap const h2 = h1;
int val = h2[0];

// https://stackoverflow.com/questions/37043078/c-overloading-array-operator