foreach.cpp
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#include <iostream>
#include <stddef.h>
class Iterator;
class Collection {
static const size_t size = 10;
int data[size];
friend class Iterator;
public:
Iterator begin();
Iterator end();
};
class Iterator {
int i;
Collection* c;
public:
Iterator(int ii, Collection* cc) : i(ii), c(cc){};
int& operator*()
{
return c->data[i];
}
Iterator& operator++()
{
++i;
return *this;
}
bool operator!=(const Iterator& o)
{
return i != o.i;
}
};
Iterator Collection::begin()
{
return Iterator(0, this);
}
Iterator Collection::end()
{
return Iterator(Collection::size, this);
}
int main()
{
Collection c;
int a = 3;
for (auto& i : c)
i = a++;
for (auto i : c)
std::cout << i << std::endl;
}